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Please help with this Calculus questions

Please help with this Calculus questions-example-1

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Answer:


\int_(0)^(1)\left( - (3 u^(9))/(2) + (2 u^(4))/(5) + 2 \right)du=(193)/(100)=1.93.

Explanation:

To find
\int_(0)^(1)\left( - (3 u^(9))/(2) + (2 u^(4))/(5) + 2 \right)du.

First, calculate the corresponding indefinite integral:

Integrate term by term:


\int{\left(- (3 u^(9))/(2) + (2 u^(4))/(5) + 2\right)d u}} =\int{2 d u} + \int{(2 u^(4))/(5) d u} - \int{(3 u^(9))/(2) d u}

Apply the constant rule
\int c\, du = c u


\int{2 d u}} + \int{(2 u^(4))/(5) d u} - \int{(3 u^(9))/(2) d u} = {\left(2 u\right)} + \int{(2 u^(4))/(5) d u} - \int{(3 u^(9))/(2) d u}

Apply the constant multiple rule
\int c f{\left(u \right)}\, du = c \int f{\left(u \right)}\, du


2 u - {\int{(3 u^(9))/(2) d u}} + \int{(2 u^(4))/(5) d u} = 2 u - {\left((3)/(2) \int{u^(9) d u}\right)} + \left((2)/(5) \int{u^(4) d u}\right)

Apply the power rule
\int u^(n)\, du = (u^(n + 1))/(n + 1)


2 u - (3)/(2) {\int{u^(9) d u}} + (2)/(5) {\int{u^(4) d u}}=2 u - (3)/(2) {(u^(1 + 9))/(1 + 9)}+ (2)/(5){(u^(1 + 4))/(1 + 4)}

Therefore,


\int{\left(- (3 u^(9))/(2) + (2 u^(4))/(5) + 2\right)d u} = - (3 u^(10))/(20) + (2 u^(5))/(25) + 2 u = (u)/(100) \left(- 15 u^(9) + 8 u^(4) + 200\right)

According to the Fundamental Theorem of Calculus,
\int_a^b F(x) dx=f(b)-f(a), so just evaluate the integral at the endpoints, and that's the answer.


\left((u)/(100) \left(- 15 u^(9) + 8 u^(4) + 200\right)\right)|_(\left(u=1\right))=(193)/(100)


\left((u)/(100) \left(- 15 u^(9) + 8 u^(4) + 200\right)\right)|_(\left(u=0\right))=0


\int_(0)^(1)\left( - (3 u^(9))/(2) + (2 u^(4))/(5) + 2 \right)du=\left((u)/(100) \left(- 15 u^(9) + 8 u^(4) + 200\right)\right)|_(\left(u=1\right))-\left((u)/(100) \left(- 15 u^(9) + 8 u^(4) + 200\right)\right)|_(\left(u=0\right))=(193)/(100)

User Eitan Rimon
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