How do you simplify cos(sin^-1(3/5)-cos^-1(1/2))?

1 Answer
May 13, 2016

(1/10)(+-4+-3sqrt3)

Explanation:

Let a = sin^(-1)(3/5) and b = cos ^(-1)(1/2).

Then, sin a = 3/5, cos a = +-4/5, cos b = 1/2 and sin b = +-sqrt3 /2

Now, the given expression is cos (a - b )

= cos a cos b + sin a sinb

=+-2/5+-3sqrt3/10=(1/10)(+-4+-3sqrt3).

The choice of sign depends on the specified ranges (if any ), for the inverse angles.a and b.