Question

Cos A+sin (270 +A) - sin (270 - A) +cos (180 +A) =

Answer 1

Answer:

0

Step-by-step explanation:

To find--->

-------------

CosA+Sin(270⁰+A)-Sin(270⁰-A)

+Cos(180⁰-A)=?

Solution--->

-------------- First we solve

Sin(270⁰+A)

(270⁰+A) is lies in fourth quadrant in which Sin is negative and in 270+ , Sin changes in to Cos ,so

Sin(270⁰+A)=-CosA

Now we solve ,Sin(270⁰-A)

(270⁰-A) lies in third quadrant in which Sin is negative and changes to Cos

Sin (270⁰-A)=-CosA

Now we solve ,Cos(180⁰-A)

(180⁰-A) lies in second quadrant in which Cos is negative and remains cos

So ,Cos (180⁰ -A)=-CosA

Now returning to original problem

CosA+Sin(270⁰+A)-Sin(270⁰-A)+

Cos(180⁰+A)

=CosA+(-CosA)-(-CosA)-CosA

=CosA-CosA+CosA-CosA

everything cancel out

= 0

Additional information--->

------------------------------------

1)cos(270-A)=-SinA

2)Cos(270+A)=-SinA

3)Sin(180-A)= SinA

Answer 2

Step-by-step explanation:

hope this helpful for you......