Tolong dibantu beserta penjelasannya yaa Trims

1)
sin^2 a - sin^2 b
_____________ = tan^2 a - tan^2 b
cos^2 a cos^2 b

sin^2 (a - b)
_____________ = tan^2 a - tan^2 b
cos^2 a cos^2 b

sin^2 a cos^2 b.....cos^2 a + sin^2 b
____________ - ______________
cos^2 a cos^2 b.....cos^2 a cos^2 b
= tan^2 a - tan^2 b

sin^2 a......sin^2 b
______ - _______ = tan^2 a - tan^2 b
cos^2 a.....cos^2 b

tan^2 a - tan^2 b = tan^2 a - tan^2 b
(TERBUKTI)

2)
2 - sec^2 b
_________ = 1 - 2sin^2 b
sec^2 b

2 - (1 / cos^2 b)
___________ = 1 - 2sin^2 b
1 / (cos^2 b)

[2 - (1 / cos^2 b)]×[cos^2 b] = 1 - 2sin^2 b
2cos^2 b - 1 = 1 - 2sin^2 b
1 - 2sin^2 b = 1 - 2sin^2 b
(TerBUKTI)