equations of tangents and normals
posted by elle on .
hi, i'd really appreciate some help solving this question! I am completely at loss here :/ The question is to:
Find the equation of the normal to y=loge(x+2) which is parallel to the line with equation y+3x-5=0
I am fine at solving these sorts of equations when they give me one equation and an provide a given x value but in this question i have no idea what i am meant to be doing... Please help!!
Put the second equation in slope intercept form
y=-3x +5 slope is -3
So what is the slope of the tangent to
so the inverse negative slope will be
- (x+2), this has to equal -3x
set them equal, and you have the x where it occurs.
Put that x into the log equation, and find y.
You have y, m, x, solve for b.