Skip to main content
Átila Correia's user avatar
Átila Correia's user avatar
Átila Correia's user avatar
Átila Correia
  • Member for 2 years, 10 months
  • Last seen this week
  • Brazil
17 votes
Accepted

Evaluate: $\int \frac{{\sin(x)}}{{\sin(x) - \cos(x)}}\,dx$

11 votes

Real integral using residue

11 votes
Accepted

If $x = 0$, then $x/x$ is undefined, right?

9 votes

After integrating $\csc^2(x)\cot(x)$ why do I get $\cot^{2}(x) = \csc^{2}(x)$?

9 votes

How to calculate a limit without using L'Hôpital's Rule

9 votes

What is $ \int_{0}^{\frac{1}{\sqrt{3}}} \sqrt{x + \sqrt{x^2 + 1}} \rm{d}x$?

8 votes
Accepted

Easiest way to show $(x^2+y^2-1)^3 = x^2y^3$ has a slope of 2 at (1,0)?

7 votes

How to solve $\cos^{40}x-\sin^{40}x=1$ for real and imaginary solutions

7 votes

Correct way to do U-sub

7 votes
Accepted

How do we prove by contradiction that, if $\langle x,y\rangle = \langle x,z\rangle$ for all $x$, then $y=z$?

7 votes

Definite integral of infinite product

7 votes

How do we calculate the derivative of $f(x) = x^{3} - 3x$?

7 votes
Accepted

Minimize $xy$ over $x^2+y^2+z^2=7$ and $xy+xz+yz=4$.

7 votes
Accepted

Prove that the solutions to $(z+1)^7 = z^7$ have same real parts

7 votes
Accepted

The solutions of the equation $ \sin{x} + \sin{3x} = \frac{8}{3\sqrt{3}} $ are?

7 votes
Accepted

Derivative of $g(x) = \frac{\log x}{\log a}$

6 votes

Limit of $\lim\limits_{x \to -3} \frac {4^\frac{x+3}{5}-1}{x+3}$, without L'Hopital's rule.

6 votes

Does the series $\sum_{n=1}^{\infty} (-1)^n(\sqrt{n+1}-\sqrt{n})$ converge or diverge?

6 votes
Accepted

Why is $\frac{1}{n}+\frac{1}{n+1}+\frac{1}{n+2}+...+\frac{1}{k}\geq \frac{1}{2}$?

6 votes
Accepted

Find all functions that satisfy the condition $f(xy,\frac{x}{y})=x^{2}-y^{2}$

6 votes

$\lim_{x \to a} x^2 = a^2$.

6 votes

What is wrong with my approach to solving $x^{\log25} + 25^{\log x} = 10\;$?

6 votes
Accepted

Finding $x+y$, given $xy= 1$, $x^2+y^2=5$, $x^3+y^3=8$

6 votes
Accepted

$f(x)=\sqrt[3]{x^2}$ derivative by defintion

6 votes
Accepted

Prove that $y=-\tan^{-1}(x)$ is a decreasing function with out the help of calculus.

5 votes
Accepted

How to prove series convergence $\sum_{n=1}^{\infty}{\frac{\cos n}{\sin 2^{-n}+n^2}}$

5 votes

Solve the equation $3^{2x^2}-2\times3^{x^2+x+6}+3^{2x+12}=0$

5 votes
Accepted

Solve $e^{-x} < \frac{1}{x^2 + 1}$

5 votes

Proving $f: \mathbb{R} \to \mathbb{R}$ such that $f(x) = \sin(x) + x$ is surjective

5 votes
Accepted

Confusion with homogenous ODE: why $[\ln (y)]'=y'/y$?

1
2 3 4 5
21