Friday

February 12, 2016
Posted by **Jenny** on Thursday, October 29, 2009 at 7:01pm.

- calculus -
**Reiny**, Thursday, October 29, 2009 at 7:29pmI would rather use the product rule than the quotient rule, so lets multiply each term by x to get

y + 8xy = x^9 + 9x

dy/dx + 8x(dy/dx) + 8y = 9x^8 + 9

dy/dx(1+8x) = 9x^8 + 9 - 8y

dy/dx = (9x^8 + 9 - 8y)/(1+8x)

plug in your point and you are done.