a. y = Cx^-4
b. y = Cx^-1/4
c. y = Cx^1/4
d. y = Cx^4
e. sin y + cos x = C
f. cos y + sin x = C
g. cos y - sin x = C
h. sin y - cos x = C
or is it none of these ?
With C an arbitrary constant, find a solution to the differential equation given: (csc x)y' + csc y = 0?
I would say none of the above. You can check my work.
You want to integrate. To do this we need to notice first that y' = dy/dx so
csc(x)(dy/dx) + csc(y) = 0
Multiply both sides by dx
csc(x)dy + csc(y)dx = 0
Divide both sides by csc(x)csc(y)
dy/csc(y) + dx/csc(x) = 0 eqn1
We know csc(z) = 1/sin(z) so eqn1 turns into
sin(y)dy + sin(x)dx = 0
Move x term to other side
sin(y)dy = -sin(x)dx
Take the integral on both sides
Ssin(y)dy = -Ssin(x)dx
-cos(y) + C1 = cos(x) + C2
Putting all constants together
-cos(y) = cos(x) +C3
or
cos(x) + cos(y) = -C3 = C
I differentiate between the constants because some people get confused if I don't.
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