Question

The equation of tangent at (2,3) on the curve y² = ax³ + b is y = 4x - 5. Find the values of a and b.

Answer 1

y² = ax³ + b

Diff. with respect to x,

Since (2, 3) lies on the curve 

y² = ax³ + b 

or 9 = 8a + b    .......(i)

Also from equation of tangent 

y = 4x - 5

slope of the tangent = 4