find an equation of the tangent line to the curve at y=2x^3+5x, (-1, 3)

Answer 1

dy/dx = 6x + 5
so at (-1,3), dy/dx = -6+5 = -1

slope = -1, point on line is (-1,3)
3 = (-1)(-1) + b in y = mx+b
2 = b

equation of tangent:
y = -x + 2