[TOC] ### Question 1: Evaluate the following function expressions #### (a) Evaluate $f(5) - f(1)$ for the function: $$ f(x) = 7x^4 - 4x^2 + 9x $$ ::: spoiler <summary> Example: </summary> ### Problem: Evaluate $f(6) - f(2)$ for the function: $f(x) = 5x^5 - 3x^3 + 6x^2 - 8x$ ### Solution: First, calculate f(6): \begin{align*} f(6) &= 5(6)^5 - 3(6)^3 + 6(6)^2 - 8(6) \\ &= 5(7776) - 3(216) + 6(36) - 8(6) \\ &= 38880 - 648 + 216 - 48 \\ &= 38240 \end{align*} Now, calculate f(2): \begin{align*} f(2) &= 5(2)^5 - 3(2)^3 + 6(2)^2 - 8(2) \\ &= 5(32) - 3(8) + 6(4) - 8(2) \\ &= 160 - 24 + 24 - 16 \\ &= 144 \end{align*} Finally, calculate $f(6) - f(2)$: \begin{align*} f(6) - f(2) &= 38240 - 144 \\ &= 38096 \end{align*} Thus, the value of $f(6) - f(2)$ is: **`38096`** ::: #### (b) Evaluate $g(3) - g(-1)$ for the function: $$ g(x) = -2x^3 + 5x^2 - 3 $$ ::: spoiler <summary> Example: </summary> We are tasked with evaluating $g(2) - g(-1)$ for the function: $$ g(x) = -3x^4 + 4x^3 - 4 $$ ### Step 1: Compute $g(2)$ We substitute $x = 2$ into the expression for $g(x)$: $$ g(2) = -3(2)^4 + 4(2)^3 - 4 $$ First, calculate the powers of 2: $$ 2^4 = 16 \quad \text{and} \quad 2^3 = 8 $$ Now substitute these values back into the equation: $$ g(2) = -3(16) + 4(8) - 4 $$ Perform the multiplications: $$ g(2) = -48 + 32 - 4 $$ Now, sum the terms: $$ g(2) = -48 + 32 = -16 $$ $$ g(2) = -16 - 4 = -20 $$ Thus, $g(2) = -20$. ### Step 2: Compute $g(-1)$ Now substitute $x = -1$ into the expression for $g(x)$: $$ g(-1) = -3(-1)^4 + 4(-1)^3 - 4 $$ First, calculate the powers of $-1$: $$ (-1)^4 = 1 \quad \text{and} \quad (-1)^3 = -1 $$ Now substitute these values back into the equation: $$ g(-1) = -3(1) + 4(-1) - 4 $$ Perform the multiplications: $$ g(-1) = -3 - 4 - 4 $$ Now, sum the terms: $$ g(-1) = -3 - 4 = -7 $$ $$ g(-1) = -7 - 4 = -11 $$ Thus, $g(-1) = -11$. ### Step 3: Compute $g(2) - g(-1)$ Now, subtract $g(-1)$ from $g(2)$: $$ g(2) - g(-1) = -20 - (-11) $$ Simplify the expression: $$ g(2) - g(-1) = -20 + 11 = -9 $$ ### Final Answer: $$ g(2) - g(-1) = -9 $$ ::: #### (c) Evaluate $h(10) - h(-10)$ for the function: $$ h(x) = 4x^5 - 2x^4 + 3x - 1 $$ ::: spoiler <summary> Example: </summary> We are tasked with evaluating $h(9) - h(-9)$ for the function: $$ h(x) = 2x^3 - 3x^2 + 4x - 5 $$ ### Step 1: Compute $h(9)$ We substitute $x = 9$ into the expression for $h(x)$: $$ h(9) = 2(9)^3 - 3(9)^2 + 4(9) - 5 $$ First, calculate the powers of 9: $$ 9^3 = 729 \quad \text{and} \quad 9^2 = 81 $$ Now substitute these values back into the equation: $$ h(9) = 2(729) - 3(81) + 4(9) - 5 $$ Perform the multiplications: $$ h(9) = 1458 - 243 + 36 - 5 $$ Now, sum the terms: $$ h(9) = 1458 - 243 = 1215 $$ $$ h(9) = 1215 + 36 = 1251 $$ $$ h(9) = 1251 - 5 = 1246 $$ Thus, $h(9) = 1246$. ### Step 2: Compute $h(-9)$ Now substitute $x = -9$ into the expression for $h(x)$: $$ h(-9) = 2(-9)^3 - 3(-9)^2 + 4(-9) - 5 $$ First, calculate the powers of $-9$: $$ (-9)^3 = -729 \quad \text{and} \quad (-9)^2 = 81 $$ Now substitute these values back into the equation: $$ h(-9) = 2(-729) - 3(81) + 4(-9) - 5 $$ Perform the multiplications: $$ h(-9) = -1458 - 243 - 36 - 5 $$ Now, sum the terms: $$ h(-9) = -1458 - 243 = -1701 $$ $$ h(-9) = -1701 - 36 = -1737 $$ $$ h(-9) = -1737 - 5 = -1742 $$ Thus, $h(-9) = -1742$. ### Step 3: Compute $h(9) - h(-9)$ Now, subtract $h(-9)$ from $h(9)$: $$ h(9) - h(-9) = 1246 - (-1742) $$ Simplify the expression: $$ h(9) - h(-9) = 1246 + 1742 = 2988 $$ ### Final Answer: $$ h(9) - h(-9) = 2988 $$ ::: --- ### Question 2: Find the following derivatives #### (a) Find $f'(x)$ for the function: $$ f(x) = 7x^4 - 4x^2 + 9x $$ ::: spoiler <summary> Example: </summary> We are tasked with finding the derivative, $f'(x)$, of the function: $$ f(x) = 6x^5 - 3x^3 + 7x $$ ### Step 1: Recall the Power Rule To differentiate the function, we will apply the **power rule** for derivatives. The power rule states: $$ \frac{d}{dx} \left( x^n \right) = nx^{n-1} $$ We will apply this rule to each term of the function. ### Step 2: Differentiate Each Term The function $f(x)$ has three terms: $6x^5$, $-3x^3$, and $7x$. We will differentiate each of them separately. #### 1. Differentiate $6x^5$ Using the power rule with $n = 5$, we differentiate $6x^5$: $$ \frac{d}{dx} \left( 6x^5 \right) = 6 \cdot 5x^{5-1} = 30x^4 $$ #### 2. Differentiate $-3x^3$ Using the power rule with $n = 3$, we differentiate $-3x^3$: $$ \frac{d}{dx} \left( -3x^3 \right) = -3 \cdot 3x^{3-1} = -9x^2 $$ #### 3. Differentiate $7x$ For the term $7x$, note that this is a linear term ($x^1$), so using the power rule with $n = 1$: $$ \frac{d}{dx} \left( 7x \right) = 7 \cdot 1x^{1-1} = 7 $$ ### Step 3: Combine the Results Now, we combine the derivatives of each term: $$ f'(x) = 30x^4 - 9x^2 + 7 $$ ### Final Answer: The derivative of the function is: $$ f'(x) = 30x^4 - 9x^2 + 7 $$ ::: #### (b) Find $g'(x)$ for the function: $$ g(x) = -2x^3 + 5x^2 - 3 $$ ::: spoiler <summary> Example: </summary> We are tasked with finding the derivative, $g'(x)$, of the function: $$ g(x) = -4x^3 + 6x^2 - 5 $$ ### Step 1: Recall the Power Rule To differentiate the function, we will apply the **power rule** for derivatives. The power rule states: $$ \frac{d}{dx} \left( x^n \right) = nx^{n-1} $$ We will apply this rule to each term of the function. ### Step 2: Differentiate Each Term The function $g(x)$ has three terms: $-4x^3$, $6x^2$, and $-5$. We will differentiate each of them separately. #### 1. Differentiate $-4x^3$ Using the power rule with $n = 3$, we differentiate $-4x^3$: $$ \frac{d}{dx} \left( -4x^3 \right) = -4 \cdot 3x^{3-1} = -12x^2 $$ #### 2. Differentiate $6x^2$ Using the power rule with $n = 2$, we differentiate $6x^2$: $$ \frac{d}{dx} \left( 6x^2 \right) = 6 \cdot 2x^{2-1} = 12x $$ #### 3. Differentiate $-5$ Since $-5$ is a constant, the derivative of a constant is 0: $$ \frac{d}{dx} \left( -5 \right) = 0 $$ ### Step 3: Combine the Results Now, we combine the derivatives of each term: $$ g'(x) = -12x^2 + 12x + 0 $$ Simplifying, we have: $$ g'(x) = -12x^2 + 12x $$ ### Final Answer: The derivative of the function is: $$ g'(x) = -12x^2 + 12x $$ ::: #### (c) Find $h'(x)$ for the function: $$ h(x) = 4x^5 - 2x^4 + 3x - 1 $$ ::: spoiler <summary> Example: </summary> We are tasked with finding the derivative, $h'(x)$, of the function: $$ h(x) = 5x^6 - 3x^4 + 4x - 2 $$ ### Step 1: Recall the Power Rule To differentiate the function, we will apply the **power rule** for derivatives. The power rule states: $$ \frac{d}{dx} \left( x^n \right) = nx^{n-1} $$ We will apply this rule to each term of the function. ### Step 2: Differentiate Each Term The function $h(x)$ has four terms: $5x^6$, $-3x^4$, $4x$, and $-2$. We will differentiate each of them separately. #### 1. Differentiate $5x^6$ Using the power rule with $n = 6$, we differentiate $5x^6$: $$ \frac{d}{dx} \left( 5x^6 \right) = 5 \cdot 6x^{6-1} = 30x^5 $$ #### 2. Differentiate $-3x^4$ Using the power rule with $n = 4$, we differentiate $-3x^4$: $$ \frac{d}{dx} \left( -3x^4 \right) = -3 \cdot 4x^{4-1} = -12x^3 $$ #### 3. Differentiate $4x$ For the term $4x$, note that this is a linear term ($x^1$), so using the power rule with $n = 1$: $$ \frac{d}{dx} \left( 4x \right) = 4 \cdot 1x^{1-1} = 4 $$ #### 4. Differentiate $-2$ Since $-2$ is a constant, the derivative of a constant is 0: $$ \frac{d}{dx} \left( -2 \right) = 0 $$ ### Step 3: Combine the Results Now, we combine the derivatives of each term: $$ h'(x) = 30x^5 - 12x^3 + 4 + 0 $$ Simplifying, we have: $$ h'(x) = 30x^5 - 12x^3 + 4 $$ ### Final Answer: The derivative of the function is: $$ h'(x) = 30x^5 - 12x^3 + 4 $$ ::: ### Question 3: Find each indefinite integral #### (a) Evaluate the indefinite integral: $$ \int x^5 \, dx = $$ ::: spoiler <summary> Example: </summary> We are tasked with evaluating the indefinite integral: $$ \int x^6 \, dx $$ ### Step 1: Recall the Power Rule for Integration To evaluate this integral, we will apply the **power rule for integration**. The power rule states: $$ \int x^n \, dx = \frac{x^{n+1}}{n+1} + C, \quad \text{for} \ n \neq -1 $$ Here, $C$ is the constant of integration, which must always be included when evaluating indefinite integrals. ### Step 2: Apply the Power Rule In this case, we have $n = 6$. Using the power rule, we increase the exponent by 1 and divide by the new exponent: $$ \int x^6 \, dx = \frac{x^{6+1}}{6+1} + C = \frac{x^7}{7} + C $$ ### Final Answer: Thus, the indefinite integral of $x^6$ is: $$ \int x^6 \, dx = \frac{x^7}{7} + C $$ ::: #### (b) Evaluate the indefinite integral: $$ \int 15x^2 \, dx = $$ ::: spoiler <summary> Example: </summary> We are tasked with evaluating the indefinite integral: $$ \int 16x^3 \, dx $$ ### Step 1: Recall the Power Rule for Integration To evaluate this integral, we will apply the **power rule for integration**. The power rule states: $$ \int x^n \, dx = \frac{x^{n+1}}{n+1} + C, \quad \text{for} \ n \neq -1 $$ Here, $C$ is the constant of integration, which must always be included when evaluating indefinite integrals. ### Step 2: Apply the Power Rule In this case, we have $n = 3$ and a constant factor of 16. The constant can be factored out of the integral, so we first rewrite the integral: $$ \int 16x^3 \, dx = 16 \int x^3 \, dx $$ Now, using the power rule for $x^3$, we increase the exponent by 1 and divide by the new exponent: $$ \int x^3 \, dx = \frac{x^{3+1}}{3+1} = \frac{x^4}{4} $$ Multiply this result by 16: $$ 16 \cdot \frac{x^4}{4} = 4x^4 $$ ### Step 3: Include the Constant of Integration Don't forget to add the constant of integration, $C$: $$ 4x^4 + C $$ ### Final Answer: Thus, the indefinite integral of $16x^3$ is: $$ \int 16x^3 \, dx = 4x^4 + C $$ ::: #### (c) Evaluate the indefinite integral: $$ \int x^{-4} \, dx = $$ ::: spoiler <summary> Example: </summary> We are tasked with evaluating the indefinite integral: $$ \int x^{-5} \, dx $$ ### Step 1: Recall the Power Rule for Integration To evaluate this integral, we will apply the **power rule for integration**. The power rule states: $$ \int x^n \, dx = \frac{x^{n+1}}{n+1} + C, \quad \text{for} \ n \neq -1 $$ Here, $C$ is the constant of integration, which must always be included when evaluating indefinite integrals. ### Step 2: Apply the Power Rule In this case, we have $n = -5$. Using the power rule, we increase the exponent by 1 and divide by the new exponent: $$ \int x^{-5} \, dx = \frac{x^{-5+1}}{-5+1} = \frac{x^{-4}}{-4} $$ ### Step 3: Simplify and Include the Constant of Integration We simplify the result as: $$ \frac{x^{-4}}{-4} = -\frac{1}{4}x^{-4} $$ Don't forget to add the constant of integration, $C$: $$ -\frac{1}{4}x^{-4} + C $$ ### Final Answer: Thus, the indefinite integral of $x^{-5}$ is: $$ \int x^{-5} \, dx = -\frac{1}{4}x^{-4} + C $$ ::: #### (d) Evaluate the indefinite integral: $$ \int 8x^{1/3} \, dx = $$ ::: spoiler <summary> Example: </summary> We are tasked with evaluating the indefinite integral: $$ \int 20x^{1/4} \, dx $$ ### Step 1: Recall the Power Rule for Integration To evaluate this integral, we will apply the **power rule for integration**. The power rule states: $$ \int x^n \, dx = \frac{x^{n+1}}{n+1} + C, \quad \text{for} \ n \neq -1 $$ Here, $C$ is the constant of integration, which must always be included when evaluating indefinite integrals. ### Step 2: Apply the Power Rule In this case, we have $n = \frac{1}{4}$ and a constant factor of 20. The constant can be factored out of the integral, so we first rewrite the integral: $$ \int 20x^{1/4} \, dx = 20 \int x^{1/4} \, dx $$ Now, using the power rule for $x^{1/4}$, we increase the exponent by 1 and divide by the new exponent: $$ \int x^{1/4} \, dx = \frac{x^{1/4 + 1}}{1/4 + 1} = \frac{x^{5/4}}{5/4} $$ ### Step 3: Simplify the Expression Simplify the fraction $\frac{1}{5/4}$ by multiplying by the reciprocal: $$ \frac{x^{5/4}}{5/4} = \frac{4x^{5/4}}{5} $$ Now, multiply by the constant 20: $$ 20 \cdot \frac{4x^{5/4}}{5} = \frac{80x^{5/4}}{5} = 16x^{5/4} $$ ### Step 4: Include the Constant of Integration Don't forget to add the constant of integration, $C$: $$ 16x^{5/4} + C $$ ### Final Answer: Thus, the indefinite integral of $20x^{1/4}$ is: $$ \int 20x^{1/4} \, dx = 16x^{5/4} + C $$ ::: ### Question 4: Find each indefinite integral #### (a) Evaluate the indefinite integral: $$ \int \frac{1 - y^2}{3y} \, dy = $$ ::: spoiler <summary> Example: </summary> We are tasked with evaluating the indefinite integral: $$ \int \frac{2y - y^3}{3y^2} \, dy $$ ### Step 1: Simplify the Expression Before applying the power rule for integration, we simplify the expression by dividing each term in the numerator by $3y^2$: $$ \frac{2y - y^3}{3y^2} = \frac{2y}{3y^2} - \frac{y^3}{3y^2} $$ Simplify each term: $$ \frac{2y}{3y^2} = \frac{2}{3y}, \quad \frac{y^3}{3y^2} = \frac{y}{3} $$ So the expression becomes: $$ \frac{2y - y^3}{3y^2} = \frac{2}{3y} - \frac{y}{3} $$ Thus, the integral becomes: $$ \int \left( \frac{2}{3y} - \frac{y}{3} \right) \, dy $$ ### Step 2: Break the Integral into Two Terms Now, break the integral into two separate integrals: $$ \int \frac{2}{3y} \, dy - \int \frac{y}{3} \, dy $$ ### Step 3: Evaluate Each Integral #### 1. Evaluate $\int \frac{2}{3y} \, dy$ This is a standard logarithmic integral. We rewrite it as: $$ \frac{2}{3} \int \frac{1}{y} \, dy = \frac{2}{3} \ln|y| $$ #### 2. Evaluate $\int \frac{y}{3} \, dy$ This is a power rule integral. Using the power rule for $y^1$, we get: $$ \frac{1}{3} \int y \, dy = \frac{1}{3} \cdot \frac{y^2}{2} = \frac{y^2}{6} $$ ### Step 4: Combine the Results and Add the Constant of Integration Now, combine the two integrals: $$ \frac{2}{3} \ln|y| - \frac{y^2}{6} + C $$ ### Final Answer: Thus, the indefinite integral of $\frac{2y - y^3}{3y^2}$ is: $$ \int \frac{2y - y^3}{3y^2} \, dy = \frac{2}{3} \ln|y| - \frac{y^2}{6} + C $$ ::: #### (b) Evaluate the indefinite integral: $$ \int \left( 4x^3 + \frac{2}{x^3} \right) \, dx = $$ ::: spoiler <summary> Example: </summary> We are tasked with evaluating the indefinite integral: $$ \int \left( 5x^4 + \frac{9}{x^4} \right) \, dx $$ ### Step 1: Rewrite the Terms Before applying the power rule, rewrite $\frac{9}{x^4}$ as a power of $x$. We can express it as: $$ \frac{9}{x^4} = 9x^{-4} $$ Thus, the integral becomes: $$ \int \left( 5x^4 + 9x^{-4} \right) \, dx $$ ### Step 2: Break the Integral into Two Terms Now, break the integral into two separate integrals: $$ \int 5x^4 \, dx + \int 9x^{-4} \, dx $$ ### Step 3: Apply the Power Rule for Integration We will now apply the **power rule for integration**, which states: $$ \int x^n \, dx = \frac{x^{n+1}}{n+1} + C, \quad \text{for} \ n \neq -1 $$ #### 1. Evaluate $\int 5x^4 \, dx$ Using the power rule with $n = 4$, we increase the exponent by 1 and divide by the new exponent: $$ \int 5x^4 \, dx = 5 \cdot \frac{x^{4+1}}{4+1} = \frac{5x^5}{5} = x^5 $$ #### 2. Evaluate $\int 9x^{-4} \, dx$ Using the power rule with $n = -4$, we increase the exponent by 1 and divide by the new exponent: $$ \int 9x^{-4} \, dx = 9 \cdot \frac{x^{-4+1}}{-4+1} = 9 \cdot \frac{x^{-3}}{-3} = -3x^{-3} $$ ### Step 4: Rewrite Without Negative Exponents and Add the Constant of Integration We rewrite $x^{-3}$ as $\frac{1}{x^3}$ and combine the two integrals: $$ x^5 - \frac{3}{x^3} + C $$ ### Final Answer: Thus, the indefinite integral of $\left( 5x^4 + \frac{9}{x^4} \right)$ is: $$ \int \left( 5x^4 + \frac{9}{x^4} \right) \, dx = x^5 - \frac{3}{x^3} + C $$ :::