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FabianMontescu
Is the answer for 1J-1k correct in the solution sheet? It says \[6 tan(3x)sec^2(3x) = 6sin(x)/ cos^3(x)\] and I don't really get that last step. I'm probably missing something.
I'd expect the answer to be \[6sin(3x)/cos^3(3x)\]
I got the same answer you did - I'm guessing it's a typo