Let S1 be the set of solutions of the inequalities x^2+ 3*x + 2 >0 and S2  be the set of solutions of the inequalities x^2 - 9>=0. I want to the set S1 union S2. What must i do? Please help me. 

Please write for me a code for the following problem.

Problem. Find all the values of m for which the function

f(x)= (x^2 + 2*m*x  + m+2)/(3*x+m)

is increasing in each interval (-infty; -m/3) and (-m/3; + infty)?

Thank you.

I want to solve the equation 12^x -6^x +6-36/(3^x)=0 with the commant

solve(12^x -6^x +6-36/(3^x)=0,x);

but i didn't receive solution x = 1. Please help me.

Problem. write the equation of the line cut the two lines d1: x = 2*t, y= -t+1, z = t-2, d2: x = -1+2*m, y = 1+m, z = 3 and perpendicular to the plane 7*x+y-4*z=0. 

This is my code. 

> restart;with(geom3d):

with(LinearAlgebra):

a:=[2*t,-t+1,t-2]:

b:=[-1+2*m,1+m,3]:

line(d1,a,t):

line(d2,b,m):

Problem. write the equation of the line cut the two lines d1: x = 2*t, y= -t+1, z = t-2, d2: x = -1+2*m, y = 1+m, z = 3 and perpendicular to the plane 7*x+y-4*z=0. 

This is my code. 

> restart;with(geom3d):

with(LinearAlgebra):

a:=[2*t,-t+1,t-2]:

b:=[-1+2*m,1+m,3]:

line(d1,a,t):

line(d2,b,m):