can someone please help me prove this
Attachments:
Answers
Answered by
1
Step-by-step explanation:
sin(x+y)sin(x-y)/cos²xcos²y
=sin²xcos²y-cos²xsin²y/cos²xcos²y
=sin²x/cos²x-sin²y/cos²y
=tan²x-tan²y
=sec²x-sec²y
Attachments:
Similar questions