COMEDK Exam 2018 Solved Paper

Given, curve is y=xsin‌x . . . (i)
At ‌‌x=‌

π

2

, we have y=‌

π

2

Slope of the tangent at x=‌

π

2

From Eq. (i), we get
‌

dy

dx

‌=sin‌x+x‌cos‌x
⇒‌‌‌

dy

dx

‌=1‌ at ‌‌

π

2

Now, equation of tangent will be
‌x−‌

π

2

=y−‌

π

2

⇒‌‌x‌=y
This will intersect X-axis at (0,0).
So, the subtangent will be =‌

π

2

−0=‌

π

2