SOLUTION: Hello, may I know how to solve this? thank you~ Find the equation of the curve by using the integration method with the gradient of the curve is 2x^2 - 5x. The point (3, 8) lies

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Question 1170598: Hello, may I know how to solve this? thank you~
Find the equation of the curve by using the integration method with the gradient of the curve is 2x^2 - 5x. The point (3, 8) lies on the curve.
Hence, find the stationary value of this curve on the point (3, 8).
Found 2 solutions by MathLover1, ikleyn:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
given:
the gradient of the curve: dy%2Fdx=+2x%5E2+-+5x
the point (3,+8)
since gradient is function degree+2, we are looking for function degree 3
f%28x%29=ax%5E3%2Bbx%5E2%2Bcx+
dy%2Fdx=+2x%5E2+-+5x ... integrating this we get, .......3%2A%281%2Fa%29=2->a=2%2F3, and 2%2A%281%2Fb%29=5->b=5%2F2
f%28x%29=+%282%2F3%29x%5E3+-+%285%2F2%29x%5E2%2Bc .......use given point (3, 8) to calculate c
8=+%282%2F3%293%5E3+-+%285%2F2%293%5E2%2Bc+
8=+18+-+45%2F2%2Bc+
c=8-18%2B45%2F2
c=+25%2F2

f%28x%29=+%282%2F3%29x%5E3+-+%285%2F2%29x%5E2%2B25%2F2



Answer by ikleyn(52810) About Me  (Show Source):
You can put this solution on YOUR website!
.

In your post, the last line  (saying  "Hence, find the stationary value of this curve on the point (3, 8).")


         * * * MAKES  no  SENSE   and is irrelevant to the rest of the post. * * *