Question

Sin^4L+sin^2Lcos^2L/1-sin^2L+sin2L/2sinLcosL

Answer 1

$sin^4L+ frac{sin^2Lcos^2L}{1-sin^2L}+ frac{sin2L}{2sinLcosL} =sin^4L+ frac{sin^2Lcos^2L}{cos^2L}+ frac{sin2L}{sin2L}= \ sin^4L+sin^2L+1$