Question

if cos²A + cos²B + cos ²c = 1 then
find the value of sin²A + sin²B + sin²C​

Answer 1

Step-by-step explanation:

If A+B+C = π , prove that :-cos²A + cos²B - cos²C ... cos²A + cos²B - cos²C = 1 - 2sinA sinB cosC. ... sin²A + {cos(180-2B) - cos( 180-2C) / 2}