My aim is to compose a tangent equation for the line y=(x-1)*(x+1)*(x+2) provided that tangent points are intersections with x-axis.
Hello,Originally Posted by totalnewbie
you know already the intersections between x-axis and curve:
(-2,0), (-1,0), (1,0).
Now you need the slope of the tangent lines:
Your function is
The gradient of the function gives the slope of the tangents:
Now use the point-slope-formula and you'll get: