2cosa Cosb, Mathematics, Formula

2cosa Cosb Formula, Mathematics Formula

जैसा कि हम सभी जानते हैं कि angles के six Trigonometric functions होते हैं और उनके नाम इस प्रकार हैं

A. Sine

B. Cosine

C. Tangent

D. Cotangent

E. Secant

F. Cosecant

These functions are in relevance the correct triangle within the following ways:

In a triangle ABC,

Sin A = Perpendicular/ Hypotenuse

Cos A = Base/ Hypotenuse

Tan A = Perpendicular/ Base

Sec A = Base/ Perpendicular

Cosec A = Hypotenuse/Perpendicular

Cot A = Hypotenuse/ Base

The formula of 2cosa Cosb

We know that,

cos(A+B)=cosAcosB–sinAsinB….. (1)

cos(A-B)=cosAcosB+sinAsinB….. (2)

Adding 1 and a pair of, we get

cos(A+B)+cos(A-B)= 2cosAcosB.