other govt exam IGNOU Junior Assistant Cum Typist (JAT) Mock Test 2023 Quantitative Aptitude Trigonometry
If (sinx + siny) = a and (cosx + cosy) = b, Then what is the value of (sinx.siny + cosx.cosy)?
1
a2 - b2 - 2
2
a + b - ab
3
(a2 + b2 -2)/2
4
a + b + ab