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Find the area between curves

Consider the following functions. f(x) = √x-7 g(x) = x-7
-1 у 24 2 4 6 8 X У 1 -1 0-2

User Sigpwned
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1 Answer

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To find the area between two curves, you must first find the points of intersection. Setting f(x) equal to g(x), You have:

√x-7 = x-7

Squaring both sides, You get:

x-7 = x^2 - 14x + 49

Simplifying and rearranging, you get:

x^2 - 15x + 56 = 0

Factoring, we get:

(x-7)(x-8) = 0

So x = 7 or x = 8.

Now we can find the area between the curves by integrating from x = 7 to x = 8:

∫[7,8] (f(x) - g(x)) dx

= ∫[7,8] (√x-7 - (x-7)) dx

= ∫[7,8] (√x - x) dx

I can simplify this integral by using u-substitution. Let u = √x and du = 1/(2√x) dx. Then:

∫[7,8] (√x - x) dx

= ∫[√7,√8] (u^2 - u^2) du (since √7=7^0.5 and √8=8^0.5)

= 0

Therefore, the area between the curves is 0.

User R Dragon
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