Nomor 8 Mohon diberi pembahasannya Terima kasih....

Lim [Tan (-x + h) - Tan (-x - h)] / h√(4 - h^2)
= Lim [Tan (h - x) - Tan -(h + x)] / h√(4 - h^2)
= Lim [Tan (h - x) + Tan (h + x)] / h√(4 - h^2)
= Lim [(sin (h - x))/(cos (h - x)) + ((sin (h + x))/(cos (h + x))] / h√(4 - h^2)
= Lim [(sin (h - x) cos (h + x) + cos (h - x) sin (h + x))/(cos (h - x) cos (h + x))] / h√(4 - h^2)
= Lim [sin ((h - x) + (h + x))]/(cos (h - x) cos (h + x)) . 1/h√(4 - h^2)
= Lim (sin 2h)/h . 1/(cos (h - x) cos (h + x) √(4 - h^2))
= 2 . 1/(cos (0 - x) cos (0 + x) √(4 - 0^2)
= 2 . 1/(cos (-x) cos x √4)
= 2 / (cos x . cos x . 2)
= 1/ cos^2 x
= sec^2 x