Because 4M and n are reciprocal, and n is the largest negative integer,

So: n=- 1, m= 1/4.

4M+2 square -8MN+5

=(4× 1/4+2)^2-8× 1/4×(- 1)+5

=9-(-2)+5

= 16

I hope I can help you. Ask if you have any questions ~ ~ ~

I wish you progress in your studies and go up a storey still higher! (*^__^*)