1.

If `sin2 theta=3/4, then sin^(3)theta+cos^(3)theta=`A. `(sqrt5)/(8)`B. `(sqrt7)/(8)`C. `(sqrt11)/(8)`D. none of these

Answer» Correct Answer - D
We have,
`sin^(3)theta+cos^(3)theta=(sintheta+cos theta)(1-(sin2 theta)/(2))`
`=sqrt(1+sin2 theta)(1-(sin2 theta)/(2))`
`=sqrt(1+(3)/(4))(1-(3)/(8))=(sqrt7)/(2)xx5/8=(5sqrt7)/(16)`


Discussion

No Comment Found