x2 - x - 2 =0
x=-1 x=2
What is the sum of the exterior angle in a hexagon?
360°
If cos30°=18/x, what is x?
20.78 cm
x3·x5=x?
8
What is called the discriminant?
D=b2 - 4ac
How long is the radius of a circumcircle of a right-angled triangle if the hypotenuse is 16 cm?
8 cm
In a right-angled triangle the acute angles are 45°. The hypotenuse is 3 cm. How long are the legs?
2.12 cm
(x2·x8):(x7·x)=?
x2
Determine the minimum place and the minimum value of this function?
f(x)= (x-2)2-1
min. place: x=2
min. value: y = -1
What is the geometric mean of 8 and 2?
4
tanx · cotx = ?
1
(x3)5:(x3·x5)=?
x7
x+y=11
x·y=30
x=5 y=6 or x=6 y=5
How big is one interior angle in a regular heptagon?
128.6°
sin 51° = cos.....
39°
Give the answer in standard form.
1.2 ·105 ·0.5·10-8=?
6·10-4
Factorize x2-x-6 .
(x+2)(x-3)
The ratio of the radius of two spheres is 2:5. What is the ratio of their volumes?
8: 125
Which function is described here?
domain: all real numbers except for 0°+k180°
range: all real numbers
zero: x = 90°+k180°
monotonously decreasing
f(x)=cotx
81-0.25+2430.2=?
4/3