Answer:
k = 30, 
Step-by-step explanation:
Since  is a solution, then it must satisfy the differential equation. So, we calculate the derivatives and replace the value in the equation. We have that
 is a solution, then it must satisfy the differential equation. So, we calculate the derivatives and replace the value in the equation. We have that 

Then, replacing the derivatives in the equation we have: 

Since  is a positive function, we have that
 is a positive function, we have that 
 .
.
Now, consider a general solution  , then, by calculating the derivatives and replacing them in the equation, we get
, then, by calculating the derivatives and replacing them in the equation, we get

We already know that r=5 is a solution of the equation, then we can divide the polynomial by the factor (r-5) to the get the other solution. If we do so, we get that (r-6)=0. So the other solution is r=6. 
Therefore, the general solution is 

 
        
             
        
        
        
Answer:   9 132
                  ----------
                     250
9.524 = 9 + 0.524 = 9 + 524       =  9 524 =    9 524:2 = 9 262 =   9 134
                                       -----------       -----------       -----------    ---------     ---------
                                         1000             1000        1000:2     500          250
 
        
                    
             
        
        
        
Answer:
0
Step-by-step explanation:

Changing x to y and y to x:

I hope I helped you.
 
        
             
        
        
        
Answer:
Step-by-step explanation: