" The value of "cos(270^(@)+theta)cos(90^(@)-theta)-sin(270^(@)-theta)cos theta" is "

Select and write the correct answer from the given alternatives in each of the following:The value of cos(270^@+theta).cos(90^@-theta)-sin(270^@-theta).costheta is=

The value of cos(270^@+theta)cos(90^@+theta)-sin(270^@-theta)costheta is.................. A) 0 B) -1 C) 1/2 D) 1

sin(270^(@)-theta).sin(90^(@)-theta)-cos(270^(@)-theta).cos(90^(@)+theta)=

sin theta cos(90^(@)-theta)+cos theta sin(90^(@)-theta)

Prove that sin (270^(@)-theta) sin (90^(@)-theta)-cos(270^(@)-theta) cos (90^(@)+theta)+1=0

Prove that: (sin(180^(@)+theta)cos(90^(@)+theta)tan(270^(@)-theta)cot(360^(@)-theta))/(sin(360^(@)-theta)cos(360^(@)+theta)cos ec(-theta)sin(270^(@)+theta))=1

Prove that (cos(90^(@)+theta)sec(270^(@)+theta)sin(180^(@)+theta))/(cosec(-theta)cos(270^(@)-theta)tan(180^(@)+theta))