cos2(x) sin4(2x)

Question

Use the power reduction formulas to rewrite the expression. (Hint: Your answer should not contain any exponents greater than 1.)
cos2(x) sin4(2x)

Answer 1

Hi Mark

 

 

cos²x sin⁴(2x)

 

1+cos(2x)        (1-cos(2x))²          

-----------   •    ------------- =

     2                       2

 

[1+cos(2x)][1-cox(2x)][1-cox(2x)]

---------------------------------------  = 

                      2

 

[1-cos²(2x)][1-cox(2x)]

---------------------------   =  

               2

 

{1-[1+cos(4x)]/2}[1-cox(2x)]

----------------------------------

                2