Answer:
yp = -x/8
Step-by-step explanation:
Given the differential equation: y′′−8y′=7x+1,
The solution of the DE will be the sum of the complementary solution (yc) and the particular integral (yp)
First we will calculate the complimentary solution by solving the homogenous part of the DE first i.e by equating the DE to zero and solving to have;
y′′−8y′=0
The auxiliary equation will give us;
m²-8m = 0
m(m-8) = 0
m = 0 and m-8 = 0
m1 = 0 and m2 = 8
Since the value of the roots are real and different, the complementary solution (yc) will give us
yc = Ae^m1x + Be^m2x
yc = Ae^0+Be^8x
yc = A+Be^8x
To get yp we will differentiate yc twice and substitute the answers into the original DE
yp = Ax+B (using the method of undetermined coefficients
y'p = A
y"p = 0
Substituting the differentials into the general DE to get the constants we have;
0-8A = 7x+1
Comparing coefficients
-8A = 1
A = -1/8
B = 0
yp = -1/8x+0
yp = -x/8 (particular integral)
y = yc+yp
y = A+Be^8x-x/8
You can you 72 which would make 2/8 18/72 and 3/9 24/72 which makes the sum 42/72.
Answer:
w=9
Step-by-step explanation:
Our equation is: 8w-15=57
Add 15 to both sides
-15 is now gone because we added 15 so it would be zero
and we have 72 because 15 plus 57 is 72
Now we have:
8w=72
Divide by 8 on both sides
8w cancels out to just w
and 72 divided by 8 is 9
And you're left with:
w=9
Y 50 I think it is I am not to sure