In △ ABC, it is known that ab = 2, ∠ C = 50 ° when ∠ B=_____ The length of. BC reaches the maximum when the In △ ABC, it is known that ab = 2, ∠ C = 50 ° when ∠ B=_____ The length of. BC reaches the maximum when the It's better to have process analysis, ideas and so on

In △ ABC, it is known that ab = 2, ∠ C = 50 ° when ∠ B=_____ The length of. BC reaches the maximum when the In △ ABC, it is known that ab = 2, ∠ C = 50 ° when ∠ B=_____ The length of. BC reaches the maximum when the It's better to have process analysis, ideas and so on

2 / sin50 = BC / Sina = BC / sin (130 degrees - b)
Sin90 degree is the maximum, then B = 130-90 = 40 degree, BC is the maximum