# trig

How do you solve for these identities:
1-sin^2è/cosè= cosè

sin^4è-cos^4è=2sin^2è-1

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1. that e symbol is suppose to be theta.

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2. LS
= 1-sin^2Ø/cosØ
= cos^2 Ø/cos
= cos Ø = RS

Ls
= sin^4Ø-cos^4Ø
= (sin^2Ø + cos^2Ø)(sin^2Ø - cos^2Ø)
= 1( sin^2Ø - (1-sin^2Ø))
= 2sin^2Ø - 1
= RS

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