Write the expression as an algebraic expression in x for x > 0. 4 tan(arccos x)

Question

Write the expression as an algebraic expression in x for x > 0.

4 tan(arccos x)

Answer 1

By definition 0 ≤ arcosx ≤ π cos(arccosx) = x; sin(arc√cosx) = √(1 - x²); 4tan(arccosx) = 4√(1 - x²)/x