Question

How do you find the slope of the tangent line to the curve `xy^3 + xy = 4` at the point (2,1)? Thank you! I really, really, appreciate your help:)?

Answer 1

`slope =-1/4`

Explanation:

`xy^3+xy=4`
`y^3+3xy^2dy/dx+y+xdy/dx=0`
slope at (2,1)
`1+6dy/dx+1+2dy/dx=0`
`8dy/dx=-2`
`dy/dx=-1/4=>slope =-1/4`