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The gradient of a function at any point (x,y) 2x - 6. If ...

The gradient of a function at any point (x,y) 2x - 6. If the function passes through (1,2), find the function.

A.

x2 - 6x - 5

B.

x2 - 6x + 5

C.

x2 - 6x - 3

D.

x2 - 6x + 7

Correct answer is D

dy/dx = 2x - 6

y = ∫ 2x - 6

y = 2x226+c
y = x2 - 6x + c
passes through (1,2)
2 = 12 - 6(1) + c
2 = 1 - 6 + c
c = 7
y = x2 - 6x + c

y = x2 -  6x + 7