(1.)  dx                here is the problem

=   -5x + C             integrate   

(2.)
 a dx             here is the problem

=    ax + C             integrate

(3.) 
10x dx            here is the problem

=      5x2 + C           integrate

(4.)  
(ax + b) dx         here is the problem

=    (1/2)ax2 + bx + C    integrate

(5.) 
(1 + 2x + 3x2 + 4x3)dx      here is the problem

=     x + x2 + x3 + x4 + C        integrate

(6.) 
(1 - x + x2 - x3 + x4)dx        here is the problem

=     x - (1/2)x2 + (1/3)x3 - (1/4)x4 + (1/5)x5 + C integrate

(7.) 
x-5 dx               here is the problem

=     (-1/4)x-4 + C           integrate

(8.) 
(12/x3)dx             here is the problem

=   
12x-3 dx          use a negative exponent

=     -6x-2 + C         integrate

(9.) 
7x-1/2 dx             here is the problem

=    14x1/2 + C           integrate
                      
(10.)  
[√x + (1/√x)]dx         here is the problem

=   
[x1/2 + x-1/2]dx           use exponents for radical signs

=    (2/3)x3/2 + 2x1/2 + C    integrate