How do you do this question?
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Step-by-step explanation:
The integral is the area under the curve. When the curve is above the x-axis, the area is positive. When the curve is below the x-axis, the area is negative. The integral equals 0, so we want to find the value of b such that the area of the quarter circle is canceled out by the area of the triangle.
Area of the quarter circle is:
A = π/4 r²
A = 9/4 π
Area of the triangle is:
A = ½ bh
9/4 π = ½ (b − 3) (b − 3)
9/2 π = (b − 3)²
b − 3 = 3√(π/2)
b = 3 + 3√(π/2)
b = 6.760