look i am sending u a trick

 plz. rate me for it......

when u want to get some inverse, then just exchange the places of x and y. u can know it if u apply pure logic. remember: (f inv.) is reflection of f on line y=x

like here-

x=(2y-pie⁾³ +2y- cosy  ...............  A      y =f(x)

this is the inv. of given fn.

now see for x=pie we get y=pie/2 as one ans.

so differentiate A....

   and put y=pie/2   as x=pie

putting values we can get ans.

if any prob. nudge me!! or else...

 

PLZ. RATE ME IF U LIKE IT. i request it to all of u....