Area — Question 3

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Question 3

Find the exact area of the region enclosed by the curves y=xandy=x2,y=\sqrt{x} \quad\text{and}\quad y=x^2, restricted to the interval 0≤x≤10\le x\le 1.

Original worksheet page 1: question and worked solution for 5-5-003
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Question 3 - Solution

First determine which curve lies above the other on [0,1][0,1]. For 0<x<10<x<1, x≥x2.\sqrt{x} \ge x^2.

Thus, the enclosed area is A=∫01(x−x2)dx.A=\int_{0}^{1}\bigl(\sqrt{x}-x^2\bigr)\,dx.

Evaluate each term: ∫01xdx=[23x3/2]01=23,\int_{0}^{1}\sqrt{x}\,dx =\left[\frac{2}{3}x^{3/2}\right]_0^1 =\frac{2}{3}, ∫01x2dx=[x33]01=13.\int_{0}^{1}x^2\,dx =\left[\frac{x^3}{3}\right]_0^1 =\frac{1}{3}.

Subtract: A=23−13=13.A=\frac{2}{3}-\frac{1}{3}=\frac{1}{3}.

13\boxed{\frac{1}{3}}

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Original worksheet page 2: question and worked solution for 5-5-003

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