Help me please~ Anyone? Question: Prove this identity. 1+cos2A-cos2B-cos2(A+B)=4sin(A+B)cosAcosB HELP! I only able to proceed 1 step only, and then, it just go back to the question again when i further solving it! Dying...
Follow Math Help Forum on Facebook and Google+
Thanks RedDog! But is there any missing? How it transform from to this ? (Perhaps can help me with explaining each other steps too?) Sorry my trigo just way too sux. Help you can teach me, please~
View Tag Cloud