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College Math! Pls help

College Math! Pls help-example-1
User Johnathan
by
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1 Answer

6 votes

Answer:

right: 11.15

left: 17.15

Explanation:

right formula:
\int _a^bf\left(x\right)dx\:\approx \Delta \:x\left(f\left(x_1\right)+f\left(x_2\right)+...+f\left(x_n\right)\right)

left formula:
\int _a^bf\left(x\right)dx\:\approx \Delta \:x\left(f\left(x_0\right)+f\left(x_1\right)+...+f\left(x_(n-1)\right)\right),


\Delta \:x\:=\:(b-a)/(n)

estimating :
\int _1^7\left((7)/(x)\right)dx , with n = 6 (number of sub-intervals in Riemann sum)

right: 1
\left(f\left(x_1\right)+f\left(x_2\right)+f\left(x_3\right)+f\left(x_4\right)+f\left(x_5\right)+f\left(x_6\right)\right) =
1\cdot \left((7)/(2)+(7)/(3)+(7)/(4)+(7)/(5)+(7)/(6)+1\right) = 11.5

left:
1\cdot \left(f\left(x_0\right)+f\left(x_1\right)+f\left(x_2\right)+f\left(x_3\right)+f\left(x_4\right)+f\left(x_5\right)\right) =


1\cdot \left(7+(7)/(2)+(7)/(3)+(7)/(4)+(7)/(5)+(7)/(6)\right) = 17.15

User AlejandroJS
by
6.5k points