1. ## Reason for different answers?

Evaluate $\int ^{2}_{-2}\frac{dx}{4+x^2}$ directly as well as by the sustitution
$x= \frac {1}{t}$ .Examine as to why the two answers do not tally?
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Evaluate $\int ^{2}_{-2}\frac{dx}{4+x^2}$ directly as well as by the sustitution
$x= \frac {1}{t}$ .Examine as to why the two answers do not tally?