Question

need step by step solution ​

Answer 1

Answer:

sin42/sec48+(cos42/cosec48)-(4/3)*(sin30)^2

=sin42/(1/cos48)+(cos42/(1/sin48))-(4/3)*((1/2)^2)

=sin42*cos48+cos42*sin48-(4*1/(3*4)

=sin42cos(90-42)+cos42*sin(90-42)-(1/3)

=sin42*sin42+cos42*cos42-(1/3)

=(sin42)^2+(cos42)^2-(1/3)

=1-1/3

=3-1/3

=2/3

so option b 2/3 is correct........