(x+2)(x-m)& lt； 0

When m & gt-2, x+2 >; 0，x & gt-2，-2 & lt； x & ltm

When m & lt-2, x+2

When m=2 and (x-2)2≥0, there is no solution.

The second question assumes that the common ratio is n, then

a 1( 1+n^2)=5,a 1n^3( 1+n^2)=40

When the two formulas are divided, n 3 = 8 and n = 2 are obtained.

a 1( 1+2^2)=5,a 1=5

A4=A 1Xn^3= 1X8=8

S5 = 1+2+4+8+ 16 = 3 1