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