Question

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

Answer 1

Assuming that 0 is a parenthesis in 1)
the sine is opp/hyp which is -4/5

Answer 2

2) looks good though

Answer 3

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! :)

Answer 4

You're welcome.