The asbscissa of the point on the curve `y=a(e^(x//a)+e^(-x//a))` where the tangent is parallel to the X-axis, is

Options

A. 0
B. `a`
C. `2a`
D. `-2a`

Answer

A

Explanation

Given equation of curve is
`y=a(e^(x//a)+e^(-x//e))`
`implies(dy)/(dt)=a(e^(x//a) . 1/a -e^(-x/a). 1/a)`
Since the tangent is parallel to X-axis.
`:.(dy)/(dx)=0`
`implies(e^(x//a)e^(-x//a))=0`
`impliese^(2x//a)=1impliese^(2x//a)=e^(0)`
`impliesx=0`