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Slope integrals for calculus, having trouble need all the help I can get

Slope integrals for calculus, having trouble need all the help I can get-example-1
User Luca Guarro
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1 Answer

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(1) The integral is straightforward; x ranges between two constants, and y ranges between two functions of x that don't intersect.


\displaystyle\int_(-2)^1\int_(-x)^(x^2+2)\mathrm dy\,\mathrm dx

(2) First find where the two curves intersect:

y ² - 4 = -3y

y ² + 3y - 4 = 0

(y + 4) (y - 1) = 0

y = -4, y = 1 → x = 12, x = -3

That is, they intersect at the points (-3, 1) and (12, -4). Since x ranges between two explicit functions of y, you can capture the area with one integral if you integrate with respect to x first:


\displaystyle\int_(-4)^1\int_(y^2-4)^(-3y)\mathrm dx\,\mathrm dy

(3) No special tricks here, x is again bounded between two constants and y between two explicit functions of x.


\displaystyle\int_1^5\int_0^{\frac1{x^2}}\mathrm dy\,\mathrm dx

Slope integrals for calculus, having trouble need all the help I can get-example-1
Slope integrals for calculus, having trouble need all the help I can get-example-2
Slope integrals for calculus, having trouble need all the help I can get-example-3
User Robins Gupta
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2.9k points