2000001507 Level: BFind the quadratic equation with real valued coefficients and one of the solutions \(\frac{1}{4}i\).\( 16x^2 +1 =0\)\( 16x^2 -1 =0\)\( x^2 -\frac{1}{4} =0\)\( x^2 +\frac{1}{4} =0\)
2000001505 Level: BWhich of the numbers below does not satisfy the equation \(2x^2=-16\)?\( \sqrt{8}(\cos{\pi} +i\sin{\pi})\)\( 2\sqrt{2}(\cos{\frac{\pi}{2}} +i\sin{\frac{\pi}{2}})\)\( 2\sqrt{2}\left(\cos{\left(-\frac{\pi}{2}\right)} +i\sin{\left(-\frac{\pi}{2}\right)}\right)\)\( 2\sqrt{2}i\)
2000001205 Level: BFind all \(x \in \mathbb{R}\) such that the given relation is true. \[ -|x|=|-x|\]\( x \in \{0\}\)\( x \in [ 0; \infty) \)\( x \in (-\infty;0] \)\(x \in \mathbb{R} \)No such \(x\) exists.
2000001204 Level: BFind all \(x \in \mathbb{R}\) such that the given relation is true. \[- |x|=-x\]\( x \in [ 0; \infty) \)\( x \in (-\infty;0] \)\(x \in \mathbb{R} \)No such \(x\) exists.\( x \in \{0\}\)
2000001203 Level: BFind all \(x \in \mathbb{R}\) such that the given relation is true. \[ |-x|=-x\]\( x \in (-\infty;0] \)\( x \in [ 0; \infty) \)\(x \in \mathbb{R} \)No such \(x\) exists.\( x \in \{0\}\)
2000001202 Level: BFind all \(x \in \mathbb{R}\) such that the given relation is true. \[ |x|=-x\]\( x \in (-\infty;0] \)\( x \in [ 0; \infty) \)\(x \in \mathbb{R} \)No such \(x\) exists.\( x \in \{0\}\)
2000001201 Level: BFind all \(x \in \mathbb{R}\) such that the given relation is true. \[ |x|=x\]\( x \in [ 0;\infty) \)\( x \in (-\infty;0] \)\( x \in\mathbb{R}\)No such \(x\) exists.\( x \in \{0\} \)
2000000705 Level: BUse the given graph of the function \(f: y=(x-2)(x-3)=x^2-5x+6\) to solve the inequality \((x-2)(x-3)< 0\).\(x \in (2;3)\)\(x \in \mathbb{R}\setminus \{2;3\}\)\(x \in (-\infty;2)\cup(3;\infty)\)\(x \in \emptyset\)
2000000704 Level: BUse the given graph of the function \(f: y=-x^2+5x\) to solve the inequality \(-x^2+5x< 0\).\(x \in (-\infty;0)\cup(5;\infty)\)\(x \in \mathbb{R}\setminus \{0;5\}\)\(x \in(0;5)\)\(x \in (0;6.25)\)
2000000703 Level: BUse the given graph of the function \(f: y=x^2-4\) to solve the inequality \(x^2-4< 0\).\(x \in (-2;2)\)\(x \in \mathbb{R}\setminus \{-2;2\}\)\(x \in (-4;0)\)\(x \in (-\infty;-2) \cup (2;\infty)\)