Math, asked by sanru, 8 months ago

proved cos^2a - sim^2b = cos(a+b)

Answers

Answered by seshathrijegasint
0

Answer:

I think your question is wrong

cos(A+B)cos(A-B)=cos²A-sin²B

this might be your question

cos(A+B)cos(A-B) = (cosAcosB - sinAsinB)(cosAcosB + sinAsinB)

{wkt (a+b)(a-b)=a²-b²}

=cos²Acos²B - sin²Asin²B

{wkt sin²A+cos²A=1}

=cos²A(1-sin²B) - (1-cos²A)sin²B

=cos²A-cos²Asin²B-sin²B+cos²Asin²B

=cos²A-sin²B

Hence the proved

Mark me as brainliest if it is correct

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