Question

if m=2/3 and n=1/2 then find the value (1) 9m^2-8n^3 (2) 81m^3 + 4n^2-9m^2n. explain.

Answer 1

1.9(2/3)^2-8(1/2)^3=9(4/9)-8(1/8)
=4-1
=3
2.81(2/3)^3+4(1/2)^2-9(2/3)^2(1/2)
=81(8/27)+4(1/4)-9(4/9)(1/2)
=3(8)+1-2
=24+1-2
=23