Replying to Trig Help
Hey I usually never do this but this problem is bugging the shit out of me.
Can anyone post how to get
cos [sin^(-1)(2/3)+2 sin^(-1)(-1/3)]
I believe it's basically asking for cos(a+2b) but I can't get to the right answer
((8 sqrt(2))/27+(7 sqrt(5))/27)
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