sin (A + B) cos (A – B) + sin (A – B) cos (A + B) =

If sin A = cos B, then A + B =

The value of cos 36° cos 54° – sin 36° sin 54° =

The value of $\frac{1}{1+cos\theta }+\frac{1}{1-cos\theta }\backslash frac\{1\}\{1+cos\backslash theta\}\; +\; \backslash frac\{1\}\{1-cos\backslash theta\}$ =

The value of $ta{n}^2\theta +ta{n}^4\theta tan^2\; \backslash theta\; +\; tan^4\; \backslash theta$ is

The value of cos ${45}^{\circ }45^\backslash circ$. cos ${30}^{\circ }30^\backslash circ$. cos ${90}^{\circ }90^\backslash circ$. cos ${60}^{\circ }60^\backslash circ$ = 

If x = a cosec$\theta \backslash theta$ and y = a cot$\theta \backslash theta$, then which of the following is true ?

If sin A= $\frac{7}{25}\backslash frac\{7\}\{25\}$,then cot A =

cos 12° – sin 78° = …………

If x = cosec θ + cot θ,.y = cosec θ – cot θ, then which of the following is true ?