B

9000062910

Level: 
B
Consider the square of the side \(4\, \mathrm{cm}\). The second square is inscribed into this first square by joining the centers of all sides. In a similar way, the third square is inscribed into the second square by joining the centers of the sides of the second square and this process continues up to infinity. Find the sum of the squares of all squares.
\(32\)
\(40\)
\(\frac{32} {3} \)
\(\infty \)

9000062907

Level: 
B
A quarter circle is an arc formed by one quarter of the full circle. An infinite spiral is built from quarter circles with an increasing radius. The radius of the first quarter circle is \(1\, \mathrm{cm}\). The radius of each quarter circle in the spiral is bigger by one half than the radius of the previous quarter circle. Find the total length of the spiral.
\(\infty \)
\(4\pi \)
\(\frac{2} {5}\pi \)
\(\frac{1} {3}\pi \)

9000063105

Level: 
B
Differentiate the following function. \[ f(x) = \frac{\sqrt{x} - 1} {\sqrt{x} + 1} \]
\(f'(x) = \frac{1} {\sqrt{x}(\sqrt{x}+1)^{2}} ,\ x > 0\)
\(f'(x) = \frac{\sqrt{x}} {(\sqrt{x}+1)^{2}} ,\ x > 0\)
\(f'(x) = \frac{2} {x(\sqrt{x}+1)^{2}} ,\ x > 0\)
\(f'(x) = \frac{1} {(\sqrt{x}+1)^{2}} ,\ x > 0\)

9000063110

Level: 
B
Differentiate the following function. \[ f(x) =\sin x(1 +\mathop{\mathrm{tg}}\nolimits x) \]
\(f'(x) =\cos x +\sin x + \frac{\sin x} {\cos ^{2}x},\ x\in \mathbb{R}\setminus\{\frac{\pi}{2}+k\pi; k\in \mathbb{Z}\}\)
\(f'(x) =\cos x +\sin x,\ x\in \mathbb{R}\setminus\{\frac{\pi}{2}+k\pi; k\in \mathbb{Z}\}\)
\(f'(x) = \frac{\sin x} {\cos ^{2}x},\ x\in \mathbb{R}\setminus\{\frac{\pi}{2}+k\pi; k\in \mathbb{Z}\}\)
\(f'(x) =\cos x + 2\sin x,\ x\in \mathbb{R}\setminus\{\frac{\pi}{2}+k\pi; k\in \mathbb{Z}\}\)

9000063101

Level: 
B
Differentiate the following function. \[ f(x) = \frac{x^{2} - 1} {x^{2} + 1} \]
\(f'(x) = \frac{4x} {(x^{2}+1)^{2}} ,\ x\in \mathbb{R}\)
\(f'(x) = \frac{-4x} {x^{2}+1},\ x\in \mathbb{R}\)
\(f'(x) = \frac{4x^{3}} {(x^{2}+1)^{2}} ,\ x\in \mathbb{R}\)
\(f'(x) = \frac{4x} {x^{2}+1},\ x\in \mathbb{R}\)