Question

The equation of the curve whose subnormal is constant ' $a$ ' is

• A. $y=ax+b$
• B. $y^2=2ax+b$
• C. $a{y}^2-x^2=a$
• D. $a{y}^2+x^2=a$

Answer 1

Answer: (B)

$L_{sN}=y\frac{dy}{dx}$
$y\frac{dy}{dx}=a$
$\Rightarrow \frac{y^2}{2}=ax+C_2$
$\Rightarrow y^2=2ax+b$