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CosA×cos2A+sinA×sin2A=cos (2A-A)​

1 Answer

6 votes

Answer:

csc

A

, as desired!

Explanation:

cos

2

A

sin

A

+

sin

2

A

cos

A

,

=

cos

2

A

cos

A

+

sin

2

A

sin

A

sin

A

cos

A

,

=

cos

(

2

A

A

)

sin

A

cos

A

,

=

cos

A

sin

A

cos

A

,

=

1

sin

A

,

=

csc

A

, as desired!

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