Question

if triangle ABC is right angled at c,then find the VALUE OF COS (A+B)

Answer 1

since ABC is right angled and angle C is 90°

therefore,

A+B=180° - C

A+B=180°-90°

A+B= 90°

Therefore,cos (A+B)=cos90°

=0

Answer 2

Answer:

The value of cos (A+B) is equal to 0.

Step-by-step explanation:

We know that a ""right angled triangle"" is a triangle in which one angle is “90°”

Given: ABC is a right angled triangle  

              i.e. A+B +C = 90⁰                                                                  

Therefore A + B =180⁰ -C

                           =180⁰- 90⁰

A +B=90⁰

Adding Cos on both the sides [In a right angled triangle the ""cosine or cos of an angle"" is the length of side which is adjacent divided by the length of hypotenuse]

Cos(A + B)=Cos(90⁰)

               =0