Question

1. Explain a scenario where we can apply cosine rule to solve triangle instead of sine rule. Give
examples if there are situations where we can applyonly sine rule but not cosine rule. When does
the ambiguity case of solving a triangle occur? Explain it with example situations where the
behaviors of number of solutions vary

Answer 1

when the units of base and hypotenuse are given, you can use cosine rule 
when the units of perpendicular and hypotenuse are given, you can use sine rule
just remember this mnemonic:
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sin = perp / hypo          cos =base / hypo       tan=perp/ base