Question

If sin A + sin B + sin C+ 3 = 0, then find the value of cos A + cos B + cos C + 10​

Answer 1

Answer:

$pls \: brainlist \: my \: answer$

Step-by-step explanation:

if sinA+sinB+sinC=3 ,

then cosA+cosB+cosC=?

sinA+sinB+sinB=1+1+1

or,

(sinA-1)+(sinB-1)+(sinC-1)=0………..(1)

Comparing the both sides of .(equation ....1)

(sinA-1)=0. => sinA= 1 or A=90°

(sinB-1)=0 => sinB=1 or B=90°

(sinC-1)=0. => sinC=1 or C=90°.

Now cosA+cosB+cosC=?

Putting. A=B=C=90°

=cos90°+cos90°+cos90°

=0+0+0

= 0