022 Exam 2 Sample B, Problem 6

Find the area under the curve of  $y=6x^{2}+2x$ between the $y$-axis and $x=2$.

Foundations:
For solving the problem, we only require the use of the power rule for integration:
$\int x^{n}dn={\frac {x^{n+1}}{n+1}}+C$
For setup of the problem we need to integrate the region between the x - axis, the curve, $x=0$ (the y-axis), and Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle x = 2} .

 Solution:

Step 1:
Set up the integral:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \int_0^{2} 6x^2 + 2x \,dx.}

Step 2:
Using the power rule we have:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \int _0^2 6x^2+2x \,dx \,=\, 6\cdot \frac{x^3}{3}+2\cdot \frac{x^2}{2} \Bigr|_{x\,=\,0}^2\,=\,2x^3+x^2 \Bigr|_{x\,=\,0}^2. }

Step 3:
Finally, we need to evaluate:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 2x^3 + x^2 \Bigr|_{x\,=\,0}^2 = (2(2)^3+(2)^2)-(0+0) = 20.}

Final Answer:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \int_0^{\,2} 6x^2 + 2x \,dx\,=\,20.}

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