Question

7 sin2 thetha + 3cos3 thetha =4 then proove that sec thetha + cosec thetha =2/√3 +2​

Answer 1

I will write theta as A

7sin²A+3cos²A=4

4sin²A+3(sin²A+cos²A)=4

4sin²A+3=4

Sin²A=1/4

SinA=1/2

Sin30=1/2

A=30

tan30=1/√3

Hence, tanA=1/√3