15 = 5 + 8d - 12
15 = 8d - 7
15 + 7 = 8d
22 = 8d
d = 2.75
Answer:
18 days.
Step-by-step explanation:
We have been given that 12 painters paint the wall of a school in 21 days.
So the wall painted by one painter will paint the wall in
As one painter will paint the wall in 252 days, so to find the number of days it will take to paint the same wall by 14 painters, we will divide time taken by one painter (252) by 14.
Therefore, it will take 18 days to paint the same wall by 14 painters.
Answer:
16 and 15
Step-by-step explanation:
First look for the fundamental solutions by solving the homogeneous version of the ODE:
The characteristic equation is
with roots and , giving the two solutions and .
For the non-homogeneous version, you can exploit the superposition principle and consider one term from the right side at a time.
Assume the ansatz solution,
(You could include a constant term <em>f</em> here, but it would get absorbed by the first solution anyway.)
Substitute these into the ODE:
is already accounted for, so assume an ansatz of the form
Substitute into the ODE:
Assume an ansatz solution
Substitute into the ODE:
So, the general solution of the original ODE is