sin x - x cos x
sin x + x cos x
cos x + x sin x
cos x - x sin x
Correct answer is D
y = x cos x
dy/dx = 1. cos x + x (-sin x)
= cos x - x sin x
Integrate \(\frac{x^2 -\sqrt{x}}{x}\) with respect to x
\(\frac{x^2}{2}-2\sqrt{x}+K\)
\(\frac{2(x^2 - x)}{3x}+K\)
\(\frac{x^2}{2}-\sqrt{x}+K\)
\(\frac{(x^2 - x)}{3x}+K\)
Correct answer is A
\(\int \frac{x^2 -\sqrt{x}}{x} = \int \frac{x^2}{x} - \frac{x^{\frac{1}{2}}}{x}\\
\int x - x^{\frac{-1}{2}}\\
=\left(\frac{1}{2}\right)x^2 - \frac{x^{\frac{1}{2}}}{\frac{1}{2}}+K\\
=\frac{x^2}{2}-2x^{\frac{1}{2}}+K\\
=\frac{x^2}{2}-2\sqrt{x}+K\)
In how many ways can 6 subjects be selected from 10 subjects for an examination
218
216
215
210
Correct answer is D
\(^{10}C_6 = \frac{10!}{(10-6)!6!}=\frac{10!}{4!6!}\\
=\frac{(10\times 9\times 8\times 7 \times 6!)}{4\times 3\times 2\times 1\times 6!}\\
=210\)
| Marks | 3 | 4 | 5 | 6 | 7 | 8 |
| Frequency | 5 | y - 1 | y | 9 | 4 | 1 |
The table above gives the frequency distribution of marks obtained by a group of students in a test. If the total mark scored is 200, calculate the value of y
15
13
11
8
Correct answer is C
Total mark scored = 200
∴200 = 15 + 4y - 4 + 5y + 54 + 28 + 8
200 = 9y + 101
200 - 101 = 9y
99 = 9y
∴y = 11
What is the mean deviation of 3, 5, 8, 11, 12 and 21?
4.7
60
3.7
10
Correct answer is A
No explanation has been provided for this answer.