` Delta ABC` में सिद्ध कीजिए कि -
` cos A + cos B + cos C = 1 + 4 sin. A/2 sin. B/2 sin. C/2`

cos A + cos B + cos C = 1 + 4sin ((A) / (2)) sin ((B) / (2)) sin ((C) / (2))

cos2B + cos2A-cos2C = 1-4sin A sin B cos C

In /_\ABC ,Prove that a cos A + b cos B + c cos C = 2a sin B sin C

cos2a-cos2b + cos2c = 1-4sin a cos b sin c

If A+B+C=(pi)/(2) , then prove that cos 2A + cos 2B + cos 2C=1+4 sin A sin B sin C .

In any Delta ABC, prove that :a cos A+b cos B+c cos C=2a sin B sin C

In a Delta ABC , 2 sinA cos B + 2 sin B cos C + 2 sin C cos A = sin A + sin B + sin C, then Delta ABC is (a) Isoceles (b) Right Angled (c) Acute (d) None of these

In a Delta ABC , 2 sinA cos B + 2 sin B cos C + 2 sin cos A = sin A + sin B + sin C, then Delta ABC is

In a Delta ABC , 2 sinA cos B + 2 sin B cos C + 2 sin cos A = sin A + sin B + sin C, then Delta ABC is