Mathematics for IGCSE & O level - Pythagoras' Theorem And Trigonometry (Section 3 - No. 49)
If sin(A) = sin(B) and A and B are angles in a triangle, what can be concluded about the relationship between A and B?
A = B
A + B = 90°
A + B = 180°
A and B are supplementary, or A=B
Vysvětlení
Sine is positive in the first and second quadrants, meaning the angles may be equal or supplementary.