Find the equation of the normal to the curve y = 4x² - 7x + 2 at the point (2, 4).

Is this right?

dy / dx =8x - 7

x-co-ordinate = 2

16 - 7 = 9 [tangent]

normal] =-1/9.

y-4 / x-2 = -1/9

9y - 36 = -x + 2

9y + x + 38 = 0

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- Dec 8th 2008, 02:14 PMdb5vryGradient of normal
Find the equation of the normal to the curve y = 4x² - 7x + 2 at the point (2, 4).

Is this right?

dy / dx =__8x - 7__

x-co-ordinate = 2

16 - 7 = 9 [tangent]

normal] =**-1/9**.

y-4 / x-2 = -1/9

9y - 36 = -x + 2

__9y + x + 38 = 0__ - Dec 8th 2008, 03:41 PMSkalkaz
Dear db5vry,

The start is perfect, the sprint is excellent, but in the last step you slid on a banane heel. - Dec 8th 2008, 03:57 PMdb5vry
Is it -34, or -38, rather than +38?

- Dec 8th 2008, 05:11 PMSkalkaz
9y - 36 = -x + 2 --> 9y+x = 38 --> 9y + x - 38 = 0