Q:For relations : → , : → such that = ⊆ , prove that ( ∘ )−1 = ^(−1) ∘ ^(−1)
How to do the proof? Is it ok to show both are subsets of each other and then say they are equal? i.e showing ( ∘ )^−1 ⊆ [^(−1) ∘ ^(−1)] and [^(−1) ∘ ^(−1)] ⊆ ( ∘ )^−1 & then say ( ∘ )−1 = ^(−1) ∘ ^(−1) Is there a other way??