Im stuck on this 2 problems.. help plz!
1.) P = {x E N/x^2 -9=0}
2.) F = {x E Q / (3x-4)(x-√2)=0}
Thank you! I'll appreciate it
1. Solve the given equations.
2. Afterwards check if the solutions belong to the given domain.
3. An example:
$\displaystyle L=\{y \in \mathbb{N}|(2y-5)(y-\sqrt{3})(y^2-1)=0\}$
A product equals zero if one of the factors equals zero:
$\displaystyle \begin{array}{ccc}2y-5=0&y-\sqrt{3}=0&y^2-1=0 \\
y=\frac52&y=\sqrt{3}&y=1\vee y=-1 \end{array}$
As you easily can see only y = 1 is a valid solution. Thus
$\displaystyle L=\{1\}$