If `sinx+siny=a` and `cosx+cosy=b` then thevalue of `sin(x+y)` is

If sin x+siny=a, cosx+cosy=b , then what is the value of cos(x-y) ?

If sinx+siny=1/2 and cosx+cosy=1 , then tan(x+y)=

Given that sinx+siny=a and cosx+cosy=b rajan derived the value of tan((x+y)/2) as follows. Fill in the blanks and write the complete solution. Given that sinx+siny=a and cosx+cosy=b .

If sin x+siny=3(cosy-cosx), then the value of (sin3x)/(sin3y), is

If sin x+siny=3(cosy-cosx), then the value of (sin3x)/(sin3y), is

If a,b, ne 0 and sinx+siny=a and cosx+cosy=b , find two values of tan((x+y)/2)