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Use the Trapezoid Rule to approximate the value of the definite integral

Use the Trapezoid Rule to approximate the value of the definite integral-example-1

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5 votes
Can u help no one is helping me ;(
Use the Trapezoid Rule to approximate the value of the definite integral-example-1
User Sebastianmehler
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3 votes

Answer:

7.0625

Step-by-step explanation:

The trapezoidal rule ( this is an approximation ) tells you that the average of the left and right endpoints should be as follows,


\int _a^bf\left(x\right)dx\:\approx (\Delta \:x)/(2)\left(f\left(x_0\right)+2f\left(x_1\right)+...+2f\left(x_(n-1)\right)+f\left(x_n\right)\right)

where
\Delta \:x\:=\:(b-a)/(n) ... at this point we can apply the Riemann Formula, in order to divide the interval 0 ≤ x ≤ 2 into n = 4 subintervals of length
\:\Delta x=(1)/(2)\:.


x_0=0,\:x_1=(1)/(2),\:x_2=1,\:x_3=(3)/(2),\:x_4=2 ,


(\Delta x)/(2)=((1)/(2))/(2)=(1)/(4)

=
(1)/(4)\left(f\left(x_0\right)+2f\left(x_1\right)+2f\left(x_2\right)+2f\left(x_3\right)+f\left(x_4\right)\right) - Let's calculate the sub intervals for each, substituting to receive our solution.


f\left(x_0\right)= 0 ( this is as 0⁴ is 0 )


2f\left(x_1\right)= 1/8 ( this is as
2\left((1)/(2)\right)^4=1/8 )


2f\left(x_2\right)=2 ( 2
* 1⁴ is 2 )


2f\left(x_3\right)= 81/8 ( this is as
2\left((3)/(2)\right)^4 = 81/8 )

And finally
f\left(x_4\right) = 16, as 2⁴ is 16. Therefore, let us plug in our solutions for each into the primary expression, and solve,


(1)/(4)\left(0+(1)/(8)+2+(81)/(8)+16\right) = 7.0625 - this is our solution. The correct answer is option c, and i hope this clarifies why.

User Emm
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3.9k points