[tex] {(7 \times 9)}^{223} \div ( {7}^{222} \times {9}^{221} )[/tex]
[tex] = ( {7}^{223} \times {9}^{223} ) \div ( {7}^{222} \times {9}^{221} )[/tex]
[tex] =( {7}^{223} \div {7}^{222} )\times( {9}^{223} \div {9}^{221}) [/tex]
[tex] = {7}^{223 - 222} \times {9}^{223 - 221} [/tex]
[tex] = {7}^{1} \times {9}^{2} [/tex]
[tex] = 7 \times 81[/tex]
[tex] =56 7[/tex]
