======T1======
Určete definiční obor funkcí a uveďte, zda jsou sudé nebo liché:
=====1=====
\( f(x) = \frac{x^2}{1 + x} \)
[[wa> asymptotes (x^2)/(1+x) , x = -10 to 10]]
<sagecell> plot( (x^2)/(1+x), (x, -10, 10) )</sagecell>

=====2.=====
\( f(x) = \sqrt{3x − x^3} \)
[[wa> plot sqrt(3x - x^3) , x = -10 to 10]]

=====3.=====
\( f(x) = (x − 2)  \sqrt{\frac{1 + x}{1 - x}} \)
[[wa> plot (x − 2) / sqrt((1 + x)/(1 - x)) , x=-10 to 10 ]]

=====4.=====
\( f(x) =\ln(x^2 − 4) \)
[[wa> plot ln(x^2 − 4) ]]

=====5.=====
\( f(x) =\ln(x + 2) + ln(x − 2) \)
[[wa>plot ln(x + 2) + ln(x − 2) ]]

=====6.=====
DELETEME \( f(x) =\ln(1 − 4x^2) \)
[[wa>plot ln(1 - 4x^2) ]]

=====7.=====
DELETEME \( f(x) = \sqrt{3x^2 − 4x + 1} \)
[[wa> plot sqrt(3x^2 − 4x + 1) ]]

=====8.=====
\( f(x) =\ln \pi/x + \arctan 2x \)
[[wa>plot ln  pi/x +  arctg 2x ]]

=====9.=====
DELETEME \( f(x) = \frac{\sqrt{x}}{\ln(2 - x)} \)
[[wa> plot       sqrt(x)/( ln(2 - x)) ]]
 
=====10.=====
DELETEME \( f (x) = ln(x^2 + 5x + 10) \)
[[wa> plot ln(x^2 + 5x + 10) , x= -10 to 10 ]]

=====11.=====
\( f(x) = 3x − x^3 \)
[[wa> plot 3x − x^3 , x=-10 to 10]]

=====12.=====
\( f(x) = \sqrt[3]{(1-x)^2} + \sqrt[3]{(1+x)^2} \)
[[wa>plot  cuberoot(1-x)^2  +  cuberoot(1+x)^2]]

=====13.=====
DELETEME \( f(x) = a^x + a^{−x}, (a > 0) \)
[[wa>plot a^x + a^−x, a=1 ]]

=====14.=====
DELETEME \( f(x) = \ln \frac{1 - x}{1 + x} \)
[[wa> plot ln      (1 - x)/(1 + x)]]

=====15.=====
DELETEME \( f(x) =\ln(x + \sqrt{1 + x^2} ) \)
[[wa>plot ln(x +  sqrt(1 + x^2) )]]