Move <math><mstyle displaystyle="true"><mi>cos</mi><mrow><mo>(</mo><mn>4</mn><mi>u</mi><mo>)</mo></mrow></mstyle></math> to the left side of the equation by subtracting it from both sides.

Apply the cosine double-angle identity.

Multiply <math><mstyle displaystyle="true"><mn>2</mn></mstyle></math> by <math><mstyle displaystyle="true"><mn>2</mn></mstyle></math> .

Subtract <math><mstyle displaystyle="true"><mi>cos</mi><mrow><mo>(</mo><mn>4</mn><mi>u</mi><mo>)</mo></mrow></mstyle></math> from <math><mstyle displaystyle="true"><mi>cos</mi><mrow><mo>(</mo><mn>4</mn><mi>u</mi><mo>)</mo></mrow></mstyle></math> .

Since <math><mstyle displaystyle="true"><mn>0</mn><mo>=</mo><mn>0</mn></mstyle></math> , the equation will always be true for any value of <math><mstyle displaystyle="true"><mi>u</mi></mstyle></math> .

All real numbers

The result can be shown in multiple forms.

All real numbers

Interval Notation:

Do you know how to Solve for u cos(2u)^2-sin(2u)^2=cos(4u)? If not, you can write to our math experts in our application. The best solution for your task you can find above on this page.