Question

Question #5cd83

Answer 1

`cos(tan^(-1) (3/4) )`

`=cos(sec^(-1) sqrt(1+(3/4)^2 ) )`

`=cos(sec^(-1) (sqrt((16+9)/4^2)) )`

`=cos(sec^(-1) (5/4 ) )`

`=cos(cos^(-1) (4/5 ) )=4/5`