B

9000120007

Level: 
B
On a map of a city, the town hall is represented by a point and a river through the city by a straight line. There are places in the city with the property that the direct distance from each place to the town hall is equal to the direct distance to the river. In the following list identify a curve which can be used to join all these places.
parabola
circle
ellipse
hyperbola
none of them

9000120005

Level: 
B
The executives of a camp organize a holiday game. For this game it is important that the direct distance kitchen - tent - fireplace is equal for all tents in the camp. Is this information enough to determine the curve passing through all the tents in the camp? Is this curve a conic? If yes, determine which conic.
Yes, all the tents are on an ellipse.
Yes, all the tents are on a circle.
Yes, all the tents are on a parabola.
Yes, all the tents are on a hyperbola.
No, we do not have enough information to draw any conclusion.

9000115609

Level: 
B
Complete the following statement: „A number is divisible by twelve if and only if ...”
it is divisible by three and four.
the sum of its digits is divisible by both two and three.
the sum of the digits is even and the last digit of this number is odd.
the sum of the digits is odd and the last digit of this number is even.

9000117401

Level: 
B
Find the intersection of the planes \(\rho \) and \(\sigma \). \[\begin{aligned} \rho \colon 2x - 5y + 4z - 10 = 0,\qquad \sigma \colon x - y - z - 2 = 0 & & \end{aligned}\]
\(\begin{aligned}[t] p\colon x& = 3t, & \\y & = -2 + 2t, \\z & = t,\ t\in \mathbb{R} \\ \end{aligned}\)
\(\begin{aligned}[t] q\colon x& = 2s - 10,& \\y & = 5s - 10, \\z & = s,\ s\in \mathbb{R} \\ \end{aligned}\)
\(\begin{aligned}[t] a\colon x& = 2u - 4,& \\y & = 2u - 4, \\z & = u,\ u\in \mathbb{R} \\ \end{aligned}\)
\(\begin{aligned}[t] b\colon x& = 3v + 1,& \\y & = v - 2, \\z & = v,\ v\in \mathbb{R} \\ \end{aligned}\)

9000108803

Level: 
B
Consider the vector \(\vec{u} = (\sqrt{3},1)\). Find the vector \(\vec{w}\) such that \(\left |\vec{w}\right | = 4\) and the angle between \(\vec{u}\) and \(\vec{w}\) is \(60^{\circ }\). Find all solutions.
\(\vec{w} = (0,4)\), \(\vec{w} = (2\sqrt{3},-2)\)
\(\vec{w} = (0,-4)\), \(\vec{w} = (\sqrt{7},-3)\)
\(\vec{w} = (0,4)\), \(\vec{w} = (\sqrt{7},3)\)
\(\vec{w} = (\sqrt{5},\sqrt{11})\), \(\vec{w} = (2\sqrt{3},-2)\)

9000111805

Level: 
B
In the following list identify a plane which is parallel to the plane \(\delta \) and the distance between both planes is \(2\). \[ \delta \colon x - 2y + 2y - 2 = 0 \]
\(\begin{aligned}[t] \beta \colon x& = -4 + 2s, & \\y& = 1 + r + s, \\z& = 1 + r,\ r,s\in \mathbb{R} \\ \end{aligned}\)
\(\gamma \colon - x + 2y - 2z - 2 = 0\)
\(\alpha \colon 2x - 4y + z - 4 = 0\)

9000108804

Level: 
B
The point \(A = [3,2]\) is rotated about the center \(B = [1,1]\) by \(60^{\circ }\). Find the coordinate of its final position. Consider both clockwise and counterclockwise direction.
\(\left [2\pm \frac{\sqrt{3}} {2} , \frac{3} {2} \mp \sqrt{3}\right ]\)
\(\left [1\pm \frac{\sqrt{3}} {2} , \frac{1} {2} \mp \sqrt{3}\right ]\)
\(\left [2\pm \frac{\sqrt{2}} {2} , \frac{3} {2} \mp \sqrt{2}\right ]\)
\(\left [1\pm \frac{\sqrt{2}} {2} , \frac{1} {2} \mp \sqrt{2}\right ]\)

9000111806

Level: 
B
In the following list identify the line such that the angle between this line and the line \(s\) is \(60^{\circ }\). \[ \begin{aligned}[t] s\colon x& = 2 + t, & \\y & = -1 - 2t, \\z & = 3 - t,\ t\in \mathbb{R} \\ \end{aligned} \]
\(\begin{aligned}[t] r\colon x& = t, & \\y & = -3 + t, \\z & = 1 + 2t,\ t\in \mathbb{R} \\ \end{aligned}\)
\(\begin{aligned}[t] q\colon x& = 1, & \\y & = -1 - t, \\z & = 3 + 2t,\ t\in \mathbb{R} \\ \end{aligned}\)
\(\begin{aligned}[t] p\colon x& = -5 - 2t,& \\y & = 2 + 4t, \\z & = 2 + 2t,\ t\in \mathbb{R} \\ \end{aligned}\)

9000111807

Level: 
B
In the following list identify a line such that the angle between this line and the plane \[ 2x - y + 3z - 5 = 0 \] is \(30^{\circ }\).
\(\begin{aligned}[t] p\colon x& = 2 + t, & \\y & = 1 + 3t, \\z & = -2t,\ t\in \mathbb{R} \\ \end{aligned}\)
\(\begin{aligned}[t] r\colon x& = -2t, & \\y & = -3 + t, \\z & = 1 - 3t,\ t\in \mathbb{R} \\ \end{aligned}\)
\(\begin{aligned}[t] q\colon x& = 2 + 3t, & \\y & = 3 - 2t, \\z & = 3 + t,\ t\in \mathbb{R} \\ \end{aligned}\)