Question

Show that (cos3 theata + isin theata)^2 = (cos3 theata + isin 3 theata)
pls give explaination

I make your answer as brainlist

Answer 1

Answer:

I am stuck on trying to prove a trig identity using De Moivre's theorem.

I have to prove,cos(3θ)=4cos3(θ)−3cos(θ)

I am not sure where to even start, I broke the LHS down tocos(3θ)+isin(3θ)

but I have no idea where to go from here, or if this is fully correct.

If I could get some pointers or a simple worked example that I could follow it would be great.

Thanks

please mark as brianlist please mark as brianlist

Answer 2

Step-by-step explanation:

$\huge \mathfrak \Red{❥ans}$