Question

Use the power reducing formulas to rewrite the following identity in terms of the first power of cosine

Answer 1

Step by step explanation:

`\sin ^4(2x)=((1-\cos (2\cdot2x))/(2))^2`
`\sin ^4(2x)=((1-\cos (4x))/(2))^2`
`\sin ^4(2x)=(1-2\cos(4x)+\cos^2(4x))/(4)`
`\sin ^4(2x)=(1-2\cos(4x)+(1+\cos(8x))/(2))/(4)`
`\sin ^4(2x)=((2-4\cos (4x)+1+\cos (8x))/(2))/(4)`
`\sin ^4(2x)=(3-4\cos (4x)+\cos (8x))/(8)`
`\sin ^4(2x)=(3)/(8)-(\cos(4x))/(2)+(\cos(8x))/(8)`
`\sin ^4(2x)=(3)/(8)-(1)/(2)\cos (4x)+(1)/(8)\cos (8x)`