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Heloo need help with this integration

Heloo need help with this integration-example-1
User Praveen Kumar K S
by
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1 Answer

14 votes
14 votes

Use the given function to find the
y-coordinate of
A.


x=2 \implies y = 10+8\cdot2+2^2-2^3 = 22

Find the equation of the line through the origin and
A. This line has slope


\mathrm{slope} = (22-0)/(2-0) = 11

and passes through (0, 0), so its equation is


y - 0 = 11 (x-0) \implies y = 11x

Then the area of the shaded region is given by the definite integral


\displaystyle \int_0^2 (y - 11x) \, dx = \int_0^2 (10 + 7x + x^2 - x^3) \, dx \\\\ ~~~~~~~~ = \left(10x + \frac72 x^2 + \frac13 x^3 - \frac14 x^4\right)\bigg|_0^2 \\\\ ~~~~~~~~ = 10\cdot2+\frac72\cdot2^2+\frac13\cdot2^3-\frac14\cdot2^4 = \boxed{\frac{98}3}

User Josias
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