If A+B+C=180 prove that cosB+cosC-cosA=4sinA/2×cosB/2×cosC/ 2-1

hope this .

r3t40

the answer for this question is : 360°

step-by-step explanation:

we have been given a triangle   we need to tell which one of these is a triangle below to map onto itself.

360° rotation is the complete rotation which eventually leads to the same figure which is given.

the correct will be, that is 360° that will cause the triangle below to map onto itself.

could you provide figure.

to complete this square you have to rotate about the origin 270 degrees clockwise.