Bob John
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 Oct10 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. Oct10 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 $P(A)$? Oct10 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 $A$? Oct9 comment Prove the $3^n < n!$ for all $n > 6$ So I multiply the RHS by 3? Oct8 comment Solving a differential equation given a general solution Can you explain why the product is -5 rather than just 5? Oct6 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? Oct6 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? Oct3 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 $t^2y'' - ty' + y = 0$?