Question

Triangle abc is a acute angled triangle then cosa+cosb+cosc

Answer 1

Step-by-step explanation:

A+B+C=180 (Angle Sum Property of a Triangle)

CosA+CosB+CosC

=Cos(A+B+C)

=Cos 180

=Cos(90+90)

=0+0

=0

Hope that it is correct.

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