y= ln4x - 6

find equasion of tangent line at x=2

y' = 1/x find y - ln4(2) - 6 = -3.9

p/s formula = y + 4.9 = x/2 equasion of tangent line @ x=2 is y= x/2 - 4.9

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- Jul 28th 2008, 11:10 AMweezie23checking answer
y= ln4x - 6

find equasion of tangent line at x=2

y' = 1/x find y - ln4(2) - 6 = -3.9

p/s formula = y + 4.9 = x/2 equasion of tangent line @ x=2 is y= x/2 - 4.9 - Jul 28th 2008, 11:49 AMSoroban
Hello, weezie23!

I can't quite follow your work . . .

Quote:

y .= .ln(4x) - 6

Find the equation of tangent line at x = 2

. . We have a point: .(2, ln(8) - 6)

The derivative is: .y' .=] .1/x

. . At x = 2, the slope is: .m = ½

The equation of the tangent is: . y - [ln(8) - 6] .= .½(x - 2)

. . which simplifies to: . y .= .½x + ln(8) - 7