Rewrite g(x) = 5 cos (2x - pi/4) -3 as k(x) a function of sine?? How do I do this?

use the identity \(cos(x) = sin(90-x)\)

Hence we can write this as

\(k(x) = 5sin(3\pi/4 - 2x) -3\)

Thanks solver

 

It is handy to know that th co in front of sine stands for complementary and that complementary angles add to 90 degrees    (pi/2 radians)

 

so

\(cosine(\theta)=sine(90-\theta)\\ cotangent(\theta)=tangent(90-\theta)\\ cosecant(\theta)=secant(90-\theta)\)