Induced map on cohomology
= Induced map on cohomology
{title2=$f^*$}
A continuous map $f:X\to Y$ induces a pullback $f^*:H^q(Y;R)\to H^q(X;R)$. It preserves sums and <cup product>[cup products], and $(g\circ f)^*=f^*\circ g^*$.
= Induced map on cohomology
{title2=$f^*$}
A continuous map $f:X\to Y$ induces a pullback $f^*:H^q(Y;R)\to H^q(X;R)$. It preserves sums and <cup product>[cup products], and $(g\circ f)^*=f^*\circ g^*$.