`f(x) = sec (tan sqrt(x))`
`therefore f(x)=(d)/(dx)[sec (tansqrt(x))]`
`=sec (tan sqrt(x)). tan (tansqrt(x)).(d)/(dx)(tan sqrt(x))`
`=sec (tansqrt(x)).tan(tansqrt(x)).sec^(2)(sqrt(x)).(d)/(dx)(sqrt(x))`
`=sec(tan sqrt(x)). tan (tansqrt(x)).sec^(2)(sqrt(x)). (1)/(2sqrt(x))`
`=(sec(tansqrt(x)). tan (tansqrt(x))sec^(2)(sqrt(x)))/(2sqrtx)`
