Kirthi Raman
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 May5 answered Funny identities May5 answered Integration: area enclosed by graph of $x^4 + y^4 = 1$ May4 answered Why is fibonacci coding useful? May4 comment Statistics : Where did this degree of freedom formula for the T distribution come from? Maybe stattrek.com/estimation/difference-in-means.aspx?tutorial=stat can help. Under the subsection titled "If you use a t score, you will need to compute degrees of freedom (DF)." May1 answered Absolute max for $f(x,y,z)=x^ay^bz^c$, with constraint $g(x,y,z)=x+y+z-1$ May1 comment Integration of $\int_0^{\pi/2} \frac{1}{\tan^2(x)}dx$? The integral does not converge $-\cot x -x$ from $0$ to $\frac{\pi}{2}$ Apr28 answered Approximating log of factorial Apr27 answered What is proxy graph? Apr26 comment How do you find all $n$ such that $\phi(n)|n$ @LHS That is correct, I just wanted to see if you could think further. Apr26 comment A book for self-study of matrix decompositions Yes that is correct. Also if you want to try out some software packages, NIST's JAMA (math.nist.gov/javanumerics/jama) is one option you might consider. Apr26 answered A book for self-study of matrix decompositions Apr23 answered $\int_0^{2\pi}\sin\frac{x}{2}\cos^2\frac{x}{2}\,dx$ Apr23 comment How do you find all $n$ such that $\phi(n)|n$ @LHS think about it. Can $n$ be prime? or Can $n$ be odd? Apr23 comment Find the sum of the roots of the equation? @vikiii the sum of the roots is the absolute value of the coefficient of $x^9$ which is the absolute value of $1+ {10 \choose 1} (-10) = 1 - 100 = -99$ and that absolute value is $99$. For instance what is the sum of the roots of $(x-2)^2+(x-4)^2=0$? which is $2x^2-12x+20=2(x^2-6x+10)=0$. The sum of the roots is the absolute value of the coefficient of $x$ and that is 6. Apr23 comment What is $\lim\limits_{k \to 0}{f(k) = 2 + k^{\frac{3}{2}}\cos {\frac{1}{k^2}}}$ @mathstudent Arturo is right (listen to the master). The limit of $cos\left(\frac{1}{k^2}\right)$ does not exist. snipurl.com/236mdru Apr22 comment How to show that $91$ is a pseudoprime to the base $3$? Oops! That was indeed a good catch (should have paid more attention) Apr22 awarded Revival Apr21 answered How to find bits you need to represent one variable? How many integers( 16 or 32 bits) you need when programming the problem? Apr21 answered How to show that $91$ is a pseudoprime to the base $3$? Apr21 awarded Necromancer