7,968 reputation
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bio website linkedin.com/in/gt6989b
location New York, NY
age 36
visits member for 3 years, 3 months
seen Dec 17 at 4:26

Mar
10
answered Manipulating an expression
Mar
10
comment Why surjectivity is defined by “for every $y$,there exist $x$ such that$ f(x)=y$” instead of “$x_1=x_2\Rightarrow f(x_1)=f(x_2)$”
@user2345215 are you suggesting to rephrase this as a basic property of a relation or a map instead of a function?
Mar
10
answered How to solve the inequality $(-K^2+13K+44)/(14-K)>0$?
Mar
10
comment How to solve the inequality $(-K^2+13K+44)/(14-K)>0$?
Not sure what you needed the $[\cdot]$ for
Mar
10
revised How to solve the inequality $(-K^2+13K+44)/(14-K)>0$?
added 43 characters in body
Mar
10
comment Why surjectivity is defined by “for every $y$,there exist $x$ such that$ f(x)=y$” instead of “$x_1=x_2\Rightarrow f(x_1)=f(x_2)$”
@user2345215 formally, you can define such a monster with a relation on the set $D \times R$ where $D,R$ denote domain and range, respectively.
Mar
10
answered Conditional probability of cards
Mar
10
comment how to sketch a distribution function and calculate F(Y)
You draw the graph of $F(y)$ first and then differentiate to compute $f(y) = F'(y)$ and draw its graph as well.
Mar
10
revised Rules of congruent equations
added 14 characters in body
Mar
10
comment Prove the following sets equalities
These look great to me.
Mar
10
comment Complex exponentiation
wouldn't this just involve choosing a particular branch for the $\log(z)$?
Mar
10
comment Proof of “Eigenvectors corresponding to different eigenvalues are linearly independent.”
@jacob If all $c_k \equiv 0$, then $v_1 = \vec{0}$, so this cannot happen. Alternatively, if $\lambda_1 = \lambda_k \forall k$, then the eigenvectors $v_k$ turn out to correspond to the same eigenvalue.
Mar
10
comment Proof of “Eigenvectors corresponding to different eigenvalues are linearly independent.”
@jacob $v_k \lambda_k = A v_k$ and so $$\sum c_k v_k \lambda_k = \sum c_k A v_k = \sum A c_k v_k = A \sum c_k v_k$$ since matrix multiplication commutes with constant multiplication.
Mar
6
answered Comparing the shape of two probability distributions
Mar
6
revised Proving the existence of a neighborhood and left inverse using calculus in $\mathbb{R}^n$
added 70 characters in body; edited title
Mar
5
answered How would I convert from frequency back to percent?
Mar
5
answered Solve for Exponent in a summation
Mar
5
comment Approximation to $\sqrt{\cos(\theta)}$?
@user86418 indeed, thanks
Mar
5
revised Calculus Exponential Function Help
added 18 characters in body
Mar
5
comment Could someone walk me through this pde?
@FraserPrice no problem, glad to be of help