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Maths — Practice Paper · Set 1
Part I — Short Answer Questions 14 × 2 = 28
Answer briefly. (Answer all questions.)
1.Show that A ∩ B = A ∩ C need not imply B = C.[2]
2.The first term of a G.P. is 1. The sum of the third term and fifth term is 90. Find the common ratio of G.P.[2]
3.Find n if ${}^{n-1}P_3 : {}^nP_4 = 1 : 9$[2]
4.Write the following sets in roster form: (i) A = {x : x is an integer and –3 ≤ x < 7} (ii) B = {x : x is a natural number less than 6} (iii) C = {x : x is a two-digit natural number such that the sum of its digits is 8} (iv) D = {x : x is a prime number which is divisor of 60} (v) E = The set of all letters in the word TRIGONOMETRY (vi) F = The set of all letters in the word BETTER[2]
5.The owner of a milk store finds that, he can sell 980 litres of milk each week at Rs 14/litre and 1220 litres of milk each week at Rs 16/litre. Assuming a linear relationship between selling price and demand, how many litres could he sell weekly at Rs 17/litre?[2]
6.Find the indicated terms in each of the sequences in Exercises 7 to 10 whose nth terms are: $a_n=\dfrac{n(n-2)}{n+3}; a_{20}$[2]
7.A solution of 8% boric acid is to be diluted by adding a 2% boric acid solution to it. The resulting mixture is to be more than 4% but less than 6% boric acid. If we have 640 litres of the 8% solution, how many litres of the 2% solution will have to be added?[2]
8.$\lim_{x\to0}\dfrac{ax+x\cos x}{b\sin x}$[2]
9.Find the values of the trigonometric functions in Exercises 6 to 10. cot $\left(-\dfrac{15\pi}{4}\right)$[2]
10.Insert two numbers between 3 and 81 so that the resulting sequence is G.P.[2]
11.If α and β are different complex numbers with $|\beta|=1$[2]
12.Vertices (0, ± 13), foci (0, ± 5)[2]
13.From the sets given below, select equal sets : A = { 2, 4, 8, 12}, B = { 1, 2, 3, 4}, C = { 4, 8, 12, 14}, D = { 3, 1, 4, 2} E = {–1, 1}, F = { 0, a}, G = {1, –1}, H = { 0, 1}[2]
14.How many 3-digit numbers can be formed by using the digits 1 to 9 if no digit is repeated?[2]
🔑 Show Answer Key — Set 1
- 1. Example: let $A=\{1\}$ , $B=\{1,2\}$ and $C=\{1,3\}$ . Then $A\cap B=A\cap C=\{1\}$ , but $B\ne C$ .
- 2. $r=3$ or $r=-3$ .
- 3. $n=9$ .
- 4. (i) $A = \{-3,-2,-1,0,1,2,3,4,5,6\}$ (ii) $B = \{1,2,3,4,5\}$ (iii) $C = \{17,26,35,44,53,62,71,80\}$ (iv) $D = \{2,3,5\}$ (v) $E = \{T,R,I,G,O,N,M,E,Y\}$ (vi) $F = \{B,E,T,R\}$
- 5. $1340$ litres.
- 6. $a_{20}=\dfrac{360}{23}$ .
- 7. More than $320$ litres but less than $1280$ litres of the 2% solution must be added.
- 8. $\dfrac{a+1}{b}$ .
- 9. $\cot\left(-\dfrac{15\pi}{4}\right)=1$ .
- 10. $9$ and $27$ .
- 11. $1$ .
- 12. $\dfrac{x^2}{144}+\dfrac{y^2}{169}=1$ .
- 13. $B=D$ and $E=G$ . No other listed sets are equal.
- 14. $504$ .