Prove that
4 cos (θ + 60) cos (θ + 30) = √3 - 2sinθ
I have said
4 cos (θ + 60) cos (θ + 30)
= 4(cosθ cos60 − sinθ sin 60) (cosθ cos30 − sinθ sin 30)
= 4(cosθ 1/2 - sinθ √3/2) (cosθ √3/2 − sinθ 1/2 )
not sure where to go now
thanks
Prove that
4 cos (θ + 60) cos (θ + 30) = √3 - 2sinθ
I have said
4 cos (θ + 60) cos (θ + 30)
= 4(cosθ cos60 − sinθ sin 60) (cosθ cos30 − sinθ sin 30)
= 4(cosθ 1/2 - sinθ √3/2) (cosθ √3/2 − sinθ 1/2 )
not sure where to go now
thanks
Hello, Gracey!
masters is right . . . you left out a "2" . . .
Prove that: .
I have said:
. . . . .
not sure where to go now . . . Really?
There is only one thing you can do ... multiply it out!
You have: .
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. . . . . .
. . . . . .
. . . . . .