#help - dy/dx

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gleaming comet
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can some1 explain the steps

crystal anchor
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root x can be written as 1/2

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dydx 3root x + 1 = dy/dx 3x^1/2 + 1 = 3/2 x^-1/2

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so our gradient

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is 3/2 x^-1/2

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5x - 10y + 7 = 0

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10 y = 5x + 7

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y = 1/2x + 7/10

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perpendicular gradient to this is -2

crystal anchor
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oh and to find the normal

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we do 1/3/(2rootx)

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which simplifies to

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.- (2 root x / 3)

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now - (2root x / 3) = -2x

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when u solve it

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u should get

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x = 9

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now to find the y coordinate

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slot it into the curve equation

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3 root 9 + 1 = 3x3 + 1 = 10

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(9, 10)

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so the gradient is -2 x

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and the point is (9, 10)

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y = -2x + c

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10 = -18 + c

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y = -2x + 28