Consider the following code snippet:
example : ∀ x y : A, x = y → PP x → PP y :=
begin
assume x y eq p,
rewrite ← eq,
exact p,
end
What is the effect of rewrite ← eq in this proof?

Question

Consider the following code snippet:  
 example :  ∀  x y : A, x = y  →  PP x  →  PP y :=  
 begin  
      assume x y eq p,  
      rewrite  ←  eq,  
      exact p,  
 end 
 What is the effect of  rewrite ←  eq  in this proof?

Accepted Answer

It rewrites the goal  PP y  to  PP x  using  eq .

Answer

It rewrites the assumption  eq  to prove reflexivity.

Answer

It rewrites the assumption  p  using  eq .

Answer

It rewrites the goal  PP x  to  PP y  using  eq .

Crowdly

Consider the following code snippet: example : ∀ x y : A, x = y → PP x...

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