9514 1404 393
Answer:
the correct choice is marked
Step-by-step explanation:
The elements are 1, 4, {4}, {9}. That is, any subset that includes 1 must include it without braces. Any subset that includes 9 must include it with braces.
{4, {9}, 1} is a subset of A
Answer:
I will study about it and tell u
Answer:
- 15x² + 7x + 1
Step-by-step explanation:
Given
2x² - 9 - 17x² + 10 + 7x ← collect like terms
= (2x² - 17x² ) + 7x + 1
= - 15x² + 7x + 1
Answer:
y = x*sqrt(Cx - 1)
Step-by-step explanation:
Given:
dy / dx = (x^2 + 5y^2) / 2xy
Find:
Solve the given ODE by using appropriate substitution.
Solution:
- Rewrite the given ODE:
dy/dx = 0.5(x/y) + 2.5(y/x)
- use substitution y = x*v(x)
dy/dx = v + x*dv/dx
- Combine the two equations:
v + x*dv/dx = 0.5*(1/v) + 2.5*v
x*dv/dx = 0.5*(1/v) + 1.5*v
x*dv/dx = (v^2 + 1) / 2v
-Separate variables:
(2v.dv / (v^2 + 1) = dx / x
- Integrate both sides:
Ln (v^2 + 1) = Ln(x) + C
v^2 + 1 = Cx
v = sqrt(Cx - 1)
- Back substitution:
(y/x) = sqrt(Cx - 1)
y = x*sqrt(Cx - 1)
