asinus

coshx*cosx=0  x=?

\(cos\ x =0\\x=\frac{\pi}{2}+\pi\cdot n\\n \in ℤ\)

\(cosh\ x=\frac{1}{2}(e^x+e^{-x})>0\\ for \ x\in \Re\)    no solution

\(solution:\)

\(coshx \cdot cosx=0\\x_1=\frac{\pi}{2} \\x_2=\frac{\pi}{2}+\pi\\x_3=-\frac{\pi}{2}\\x_4=-(\frac{\pi}{2}+\pi) \)

\(x=\frac{\pi}{2}+\pi\cdot n\)     Thank you! C.

\( for\ n \in ℤ\)

  !

fünfdrittel - einhalb ist gleich?

\(\frac{5}{3}-\frac{1}{2}\)

\(=\frac{5\cdot2}{3\cdot2}-\frac{1\cdot3}{3\cdot2}\)

\(=\frac{10-3}{6}\)

\(=\frac{7}{6}\)

  !

Thank you Chris, you have explained to me well.
I have looked at chance and probability as the same.
Sometimes it is not easy for me to understand English properly.
You surely look at this.
Greeting asinus: -)

Thank you would not have been inappropriate.

the multiples of i 

i^9  i^100  i^2017

how to answer these questions

\(i=\sqrt{-1}\)

i^1=  i

i^2=-1

i^3= -i

i^4= 1

i^5=  i

\(i^9 =(i^3)^3=(-i)(-i)(-i)=(-1)(-i)=i\)

\(i^{100}=((i^5)^5)^4=(i^5)^4=i^4=1\)

\(i^{2017}=(i)(i^{2016})\)  ?

Excuse me. Unfortunately I do not know.

  !

suatu fungsi dengan rumus f(x)=ax+b jika f(4)=5 dan f(-2)= -7 , maka tentuka rumus fungsi f(x)?

A function f(x) = ax + b.    If  f(4) = 5 and  f(-2) = -7, then the function is f(x) = ?

\( f (x) = ax + b\)

\( f (4) = a\cdot 4 + b=5\)

\(a=\frac{5-b}{4}\)

\( f (-2) = -2\cdot a + b=-7\)

\(a=\frac{-7-b}{-2}\)

\(\frac{-7-b}{-2}=\frac{5-b}{4}\)

\(-28-4b=2b-10\)

\(6b=-18\\\color{blue}b=-3\)

\(a=\frac{5-b}{4}\\a=\frac{5+3}{4}\)

\(a=2\)

\(\large f(x)=2x-3\)

  ! Thank you C.

where is the fraction button?

\(Give\ [LaTeX] \)

\( Delete\)   x = {-b \pm \sqrt{b^2-4ac} \over 2a}

\(operate \ [\ \underline{Math}\ ]\)

\(operate \ [\ \Box/\Box\ ]\)

\(Give \ numerator \ and \ denominator \ in\) \\(frac\) {1}{3}

\(Give \ OK\)

\(\frac{1}{3}\)

  !

We compare two surfaces.
The sum of the two surfaces is not interesting (given the given question).

write each expression as a single logarithm in simplest form. state any restrictions on the variable.

\(log_3\frac{\sqrt{x}}{x}+log_3\sqrt[5]{x^2}+\frac{3}{2}log_3x\)

\(=log_3\frac{\sqrt{x}\cdot \sqrt[5]{x^2}\cdot \sqrt{x^3}}{x}\)

\(=log_3(x^{\frac{1}{2}+\frac{2}{5}+\frac{3}{2}-1})\) 

\(=log_3(x^{1.4})\)

\(=1.4\times log_3(x)\)

  !

If the rate of reaction is 5 x 10-9 mol/s, how many grams of magnesium will be used up in 5 min?

\(\large 5\times10^{-9}\frac{mol}{s}\times\frac{24.305g\ Mg}{mol}\times 5min \times\frac{60s}{min}=3.64575\cdot 10^{-5}g\ Mg\)

  !