" If "y=(1+sin x-cos x)/(1+sin x+cos x)" then "y_(2)=

If y =a cos (sin x) + b sin (sin x) then y _(2) + (tan x) y_(1)=

If y = Tan ^(-1) ((cos x- sin x)/(cos x + sin x)) then (d ^(2) y)/(dx ^(2))=

If y=(sin^(-1)x-cos^(-1)x)/(sin^(-1)x+cos^(-1)x)," then "(dy)/(dx)=

cos (x + y), sin (x + y), - cos (x + y) sin (xy), cos (xy), sin (xy) sin2x, 0, sin2y] | = sin2 (x + y)

If tan A=(x sin B)/(1-cos B)tan B=(y sin A)/(1-y cos A) then (x)/(y)=

I : If cos x + cos y=1/3 , sin x+sin y=1//4 " then " cos (x+y)=7//25 II : If cos x + cos y=1//3 , sin x + sin y=1//4 " then " sin(x+y)=24//25

Prove that (i) 2 cos x cos y=cos (x+y)+cos (x-y) (ii) -2 . sin x sin y=cos (x+y)-cos (x-y) (iii) 2 sin x cos y=sin (x+y)+sin (x-y) (iv) 2 cos x sin y=sin (x+y)-sin (x-y)

Prove that : (sin (x+y))/(sin (x-y) )= (sin x. cos y + cos x . Sin y)/(sin x. cos y-cos x. sin y)

Prove that : (sin (x+y))/(sin (x-y) )= (sin x. cos y + cos x . Sin y)/(sin x. cos y-cos x. sin y)