prove that 1/tan theta + cot theta - 1/1 + sin theta + 1/1 - sin theta = 2 sec square theta
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Hello friend,
instead of theta i am using ' a ' okay!
= sin a (1 + tan a ) + cos a (1+ cot a)
= sin a(1+sin a /cos a ) +cos a(1+ cos a /sin a)
= sin a (cos a +sin a )cos a + cos a (sin a +cos a)/sin a
taking (cos a + sin a) common
= (sin a /cos a +cos a / sin a)(cos a + sin a )
= (sin^2 a +cos^2 a)(cos a+ sin a )/sin a . cos a
by using sin^2 a +cos^2 a =1 ,
= (cos a +sin a)/ sin a .cos a
= cos a/sin a.cos a + sin a /cos a. sin a
= 1/sin a +1/ cos a
= cosec a +sec a
instead of theta i am using ' a ' okay!
= sin a (1 + tan a ) + cos a (1+ cot a)
= sin a(1+sin a /cos a ) +cos a(1+ cos a /sin a)
= sin a (cos a +sin a )cos a + cos a (sin a +cos a)/sin a
taking (cos a + sin a) common
= (sin a /cos a +cos a / sin a)(cos a + sin a )
= (sin^2 a +cos^2 a)(cos a+ sin a )/sin a . cos a
by using sin^2 a +cos^2 a =1 ,
= (cos a +sin a)/ sin a .cos a
= cos a/sin a.cos a + sin a /cos a. sin a
= 1/sin a +1/ cos a
= cosec a +sec a
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