Write the double angle formula for cosine in two alternate forms by filling in the blanks using a trig identity or simplifying your answer at each step.

a) cos(2t) = 1 - sin^2t = 1 ( "fill in the blank") = "fill in the blank"

b) cos(2t) = 2cost^2(t) - 1 = 2cos^2(t) - ( "fill in the blank") = fill in the blank.

Question

Write the double angle formula for cosine in two alternate forms by filling in the blanks using a trig identity or simplifying your answer at each step. 

a) cos(2t) = 1 - sin^2t = 1 ( "fill in the blank") =  "fill in the blank"

b) cos(2t) = 2cost^2(t) - 1 = 2cos^2(t) - ( "fill in the blank") = fill in the blank.

anonymous · Answer

Im trying to use the pythagorean identities but its always saying im wrong O.o

anonymous · Answer

@lgbasallote  can you help :/

lgbasallote · Answer

this doesn't make sense... cos(2t) isn't equal to 1- sin^2 t...can you explain your question?

anonymous · Answer

2cos^2x-1

anonymous · Answer

Its an interactive website, ill take a screen shot wait

anonymous · Answer

attachment

anonymous · Answer

Its some pre cal stuff just as a review. but even then i just cant seem to get it "-_-

anonymous · Answer

cos2t= 2cos^2 (x) -1 = 1- 2sin^2 (x)=cos^2 (x)-sin^2(x)

lgbasallote · Answer

that's a totally different thing

anonymous · Answer

I didnt write it down correctly? sigh im sorry

anonymous · Answer

oh i forgot the 2!!!

anonymous · Answer

the answer is already there,

anonymous · Answer

well what do you mean?

anonymous · Answer

the fill in the blank?

anonymous · Answer

i have already given the asnswer, just look at it to fill in the missing blanks