49m 4 n−21 m 6 n 2 space, start fraction, 49, m, start superscript, 4, end superscript, n, minus, 21, m, start superscript, 6, end superscript, n, start superscript, 2, end superscript, divided by, 7, m, start superscript, 2, end superscript, n, start superscript, 4, end superscript, end fraction which expression is equivalent to the above for all m> 1m> 1m, is greater than, 1 and n> 1n> 1n, is greater than, 1