Question

For which value of m is the line y = mx + 1 a tangent to the curve y² = 4x?

विकल्प

• `1/2`

• 1

• 2

• 3

Answer 1

1

Explanation:

y = mx + 1 ...........(1) and

y² = 4x .......(2)

Substituting (1) in (2):

(mx +1)² = 4x

m²x² + (2m − 4)x + 1 = 0 ........(3)

As line is tangent to the curve

line touches the curve at only one poin

(2m − 4)² − 4m² = 0

m = 1