Question

explain why tanA tanB/1-tanAtanB is undefined when A=pie/6, B=pie/3?

Answer 1

tanA tanB/1-tanAtanB
When A=π/6 and B=π/3
put the value
tanπ/6 tanπ/3 /1- tanπ/6 tanπ/3
1/√3 ×√3
   1-1/√3×√3
1/1-1⇒1/0=∞=which cannot be defined

Answer 2

pie/6=30
pie/3=60
tan60*tan30//1-tan60tan30
=$\frac{ \sqrt{3} }{ \sqrt{3} } /1- \frac{ \sqrt{3} }{ \sqrt{3} }$

=1/0
=which is nothing but undefined