# calculus

find cosx and sinx if tanx = 4

1. sin ( x ) = + OR / [ tan (x) /sqrt ( 1 + tan ^2 (x)]

sin ( x ) = + OR - [ 4/ sqrt ( 1 + 4 ^2 ) ]

sin ( x ) = + OR - m4/ sqrt ( 1 + 16 )

sin ( x ) = + OR - 4/ sqrt ( 17)

cos ( x ) = + OR / 1 /sqrt ( 1 + tan ^2 (x)

cos( x ) = + OR - 1 / sqrt ( 17)

If you want all trigonometric identities in google type:

wikipedia List of trigonometric identities

posted by Bosnian
2. cos ( x ) = + OR - 1 /sqrt ( 1 + tan ^2 (x) )

posted by Bosnian

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