Question

find line tangent to y=xcosx at point (pi, -pi)

Answer 1

tangent is -1

Answer 2

just typed y=-1 in. says incorrect

Answer 3

the equation should be y = -x

Answer 4

yep, ty.

Answer 5

this is how I calculated it. y = xCosx is the function. taking it's derivative gives the slope to be dy/dx = cosx, which when evaluated at x =pi gives -1.

now equation of line is y=mx+c, we know m=-1 and putting y = -pi and x = pi we get c =0. thus the equation of line tangent to the curve is y =-x

Answer 6

ok