Question

Find i) tan75 ii) tan 15 using the relation
tan(A+B)= tan A+ tan B / 1-tanAtanB
tan(A-B) = tan A-tan B / 1+tanAtanB

Answer 1

tan(75) = tan(30+45) =$\frac{tan(45) +tan(30)}{1 - tan(45) tan(30)} = 3.732$

tan(15) = tan(45-30) = $\frac{tan(45) - tan(30)}{1 + tan(45) tan(30)} = 0.2679$