Question

plz prove the above​

Answer 1

As taking L.H.S

As, tan(A+B)= tan(A+B)/1-tanAtanB

here, A=69° and B=66°

therefore,

tan(69° + 66°)/1 - tan69°tan66° = tan(69°+66°)

i.e, tan(66°+69°)

=tan(135°)

-tan(45°)

i.e, (-1)

Ans is (-1)..

hence, proved