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seen Oct 10 '12 at 19:24

Oct
10
comment Prove that $f$ is onto if and only if $g$ is onto
I understand the image, but I don't know how to apply the math behind it.
Oct
10
comment Prove that $f$ is onto if and only if $g$ is onto
How can I find the preimage in $P(A)$? By applying the definition of $g(S)$ for $P(A)$?
Oct
10
comment Prove that $f$ is onto if and only if $g$ is onto
How can I show that $g$ is onto if it's domain is just the power set of $A$?
Oct
9
comment Prove the $3^n < n!$ for all $n > 6$
So I multiply the RHS by 3?
Oct
8
comment Solving a differential equation given a general solution
Can you explain why the product is -5 rather than just 5?
Oct
6
comment Finding the general solution of a sixth degree differential equation
Ok, that makes sense. But why is $i = -4\pm 3i$? More specifically, why are we assigning $i$ the value of the complex root, is that what it represents?
Oct
6
comment Finding the general solution of a sixth degree differential equation
Where does the 1/2 come from in the first $y_1$? Also, why do we substitute $e^{rx}$ into the differential equation?
Oct
3
comment Show that $y(t) = t$ and $g(t) = t \ln(t)$ are linearly independent
Does this allow me to write a general solution for $t^2y'' - ty' + y = 0$?