If cos - - cos - -a- sin- - sin - - b- then cos- - - is equal to

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Sign of Trigonometric Ratios in Different Quadrants

If cos α + ...

Question

If $c o s α + c o s β = a, s i n α + s i n β = b$ , then $c o s (α - β)$ is equal to

\frac{2 a b}{a^{2} + b^{2}}

No worries! We‘ve got your back. Try BYJU‘S free classes today!

\frac{a^{2} b^{2}}{a^{2} - b^{2}}

No worries! We‘ve got your back. Try BYJU‘S free classes today!

\frac{a^{2} + b^{2} - 2}{2}

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

\frac{b^{2} - a^{2}}{a^{2} + b^{2}}

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

Suggest Corrections

Similar questions

s i n α + s i n β = a

c o s α + c o s β = b,

s i n (α + β) = \frac{2 a b}{a^{2} + b^{2}}

c o s (α + β) = \frac{b^{2} - a^{2}}{b^{2} + a^{2}}

If $s i n α + s i n β = a a n d c o s α + c o s β = b$ , prove that

(i) $s i n (α + β) = \frac{2 a b}{a^{2} + b^{2}}$

(ii) $c o s (α - β) = \frac{a^{2} + b^{2} - 2}{2}$

sin α + sin β = a

cos α + cos β = b

tan \frac{α - β}{2} = \pm \sqrt{\frac{x - a^{2} - b^{2}}{a^{2} + b^{2}}}

x

If $s i n α + s i n β = α$ and $c o s α - c o s β = b$ , then $t a n \frac{α - β}{2} =$

sin α + sin β = a

cos α + cos β = b

sin α + β = \frac{m a b}{a^{2} + b^{2}}

m

Join BYJU'S Learning Program