Incorrect. Begin by factoring the number under the radical in terms of products of square numbers. In this case, $\displaystyle{1296}={4}\cdot{4}\cdot{81}\usepackage{cmbright}\Huge\$ , so $\displaystyle\sqrt{{1296}}=\sqrt{{{{2}}^{{2}}\cdot{{2}}^{{2}}\cdot{{9}}^{{2}}}}\usepackage{cmbright}\Huge\$ . Does this help you find the square root of 1296?