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wach
Some simple inverse trig functions. Can you check my answers? 1. sin(tan^-1 -4/30 = -3/5 2. sin^-1(sin(5pi/4) = -pi/4
Assuming that 0 is a parenthesis in 1) |dw:1349413412829:dw|the sine is opp/hyp which is -4/5
2) looks good though
Oh, right. Because tan inverse exists only in the 4th and 1st quadrant, thus it's -4 instead of -3. Ok. Cool, makes sense. Thanks! :)