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Please i need help for this calculus

Please i need help for this calculus-example-1
User Dirkgroten
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1 Answer

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9 votes

Explanation:

First thing first, let find the x value of where P and Q both meet y=5, we know that y=5, and y=2x^2+7x-4, so using transitive law,


5 = 2 {x}^(2) + 7x - 4


2 {x}^(2) + 7x - 9


2 {x}^(2) - 2x + 9x - 9


2x(x - 1) + 9(x - 1)


(2x + 9)(x - 1) = 0


x = 1


2x + 9 = 0


x = - (9)/(2)

Now, to find the gradient of the curve let take the derivative of both sides


5 = 2 {x}^(2) + 7x - 4


0 = 4x + 7


4x + 7

Plug in -9/2, let call that point P


4( ( - 9)/(2) ) + 7 = - 11

Plug in 1, let call that point Q


4(1) + 7 = 11

So the gradient of the curve at point P (-9/2,5) is -11

The gradient of the curve at point Q (1,5) is 11.

User Shawn Wang
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