Application of DerivativeHard

Question

The point at which the tangent to the curve y = x3 + 5 is perpendicular to the line x + 3y = 2 are-

Options

A.(6, 1), (-1, 4)
B.(6, 1) (4, -1)
C.(1, 6), (1, 4)
D.(1, 6), (-1, 4)

Solution

Let point (x1, y1)
y = x3 + 5
= 3x2
 
= 3 x21
It is ⊥  to x + 3y - 2 = 0
So 3 x21 × - = -1
x1 = ±1
x1 = 1,        y1 = 6
x1 = -1,       y1 = 4
(1, 6) and (-1, 4)

Create a free account to view solution

View Solution Free
Topic: Application of Derivative·Practice all Application of Derivative questions

More Application of Derivative Questions