Skip to main content

2

Q1.

Solution

Q2.

Solution

Q3. Let A = {2, 4, 6, 8, 10} and B = {(a, b) : a divides b; a , b  A}. Write the elements of B.

Solution

B = {(2, 2), (2, 4), (2, 6), (2, 8), (2, 10), (4, 8)}
Q4. If the set A has 4 elements and the set B = {4, 5, 6}, then find the number of elements in (A  B).

Solution

Since, n(A) = 4 and n(B) = 3 Therefore n((A  B) = 12
Q5. If A = {1, 2, 3}, B = {4}, C = {5}, verify that A  (B  C) = (A  B)  (A  C)

Solution

(B  C) = {4, 5} So, A  (B  C) = {(1, 4), (1, 5), (2, 4), (2, 5), (3, 4), (3, 5)} Now    (A  B) = {(1, 4), (2, 4), (3, 4)} And    (A  C) = {(1, 5), (2, 5), (3, 5)} Therefore, (A  B)  (A  C) =  {(1, 4), (1, 5), (2, 4), (2, 5), (3, 4), (3, 5)} Hence, A  (B  C) = (A  B)  (A  C)
Q6. The function f is defined by f open parentheses x close parentheses equals open curly brackets table row cell 2 minus x comma space i f space x less than 0 end cell row cell 2 comma space i f space x equals 0 end cell row cell x plus 2 comma space i f space x greater than 0 end cell end table close Draw the graph of f(x).

Solution

Here, f(x) = 2 – x, x < 0, this gives f(-3) = 5, f(-2) = 4, f(-1) = 3,… f(3) = 5, f(2) = 4, f(1) = 3,… for f(x) = x + 2, x > 0. Thus the graph of f is as follows-
Q7. If R is the relation ‘is less than’ from A = {2, 4, 6, 8, 10} and B = {2, 6, 10}, write down the Cartesian product corresponding to R.

Solution

Clearly R = {(a, b)  A  B; a < b}  R = {(2, 6), (2, 10), (4, 6), (4, 10), (6, 10), (8, 10)}
Q8. Let X = {2, 4, 6}, Y = {3, 5}and Z= {2, 3}, then find X  (Y  Z).

Solution

(Y  Z) = {2, 3, 5} Therefore, X  (Y  Z) = {(2, 2), (2, 3), (2, 5), (4, 2), (4, 3), (4, 5), (6, 2), (6, 3), (6, 5)}
Q9.

Solution

Q10. Let R = {(3,1),(3, 5), (5, 1), (5, 5)} is a relation from A = {2,3,4,5} to B = {1,3, 5}  Find the Codomain of R.

Solution

Codomain of R = {1, 3, 5}
Q11.

Solution

Q12. If A = {x, y}, then find A  A  A.

Solution

A  A  A = {(x, x, x ), (x, x, y), (x, y, x), (x, y, y), (y, x, x), (y, x, y), (y, y, x) (y, y, y)}
Q13.

Solution

Q14. Let f: R  R be defined as                                                                   Show that f is not a function.

Solution

W h e n space x less than 5 comma space w e space h a v e space f open parentheses x close parentheses equals 3 x plus 4
W h e n space x greater than 5 comma space w e space h a v e space f open parentheses x close parentheses equals x plus 5
B u t space w h e n space x equals 5 comma space w e space h a v e comma space f open parentheses 5 close parentheses equals 3 open parentheses 5 close parentheses plus 4 equals 19
A l s o comma space f open parentheses 5 close parentheses equals 5 plus 5 equals 10
I t space i s space c l e a r space t h a t space f open parentheses 5 close parentheses space i s space n o t space u n i q u e l y space d e t e r m i n e d space a n d
h e n c e space f space i s space n o t space a space f u n c t i o n.
Q15.

Solution

Q16. Determine the domain and range of the relation R defined by R = {(x + 2, x + 4): x  {0, 1, 2, 3, 4}

Solution

Domain = {2, 3, 4, 5, 6}, Range = {4, 5, 6, 7, 8}
Q17. Draw the graph of the function y = x2 + 4x + 6.

Solution

The given function is y = x2 + 4x + 6    = (x + 2)2 + 2 The graph of the given function will be a parabola. The parabola will open upward. The least value of (x + 2)2 is zero and will be so when x = -2. When x = -2, y = 2 The vertex is (-2, 2). So, the graph of the given function is as follows.  
Q18. Determine the domain and range of the following relation on R: R equals open curly brackets open parentheses x comma 2 over x close parentheses : 0 less than x less than 8 comma space x element of N close curly brackets

Solution

R equals open curly brackets open parentheses x comma 2 over x close parentheses : 0 less than x less than 8 comma space x element of N close curly brackets Domain of R = {1, 2, 3, 3, 5, 6, 7} R a n g e space o f space R equals open curly brackets 2 comma 1 comma 2 over 3 comma 1 half comma 2 over 5 comma 1 third comma 2 over 7 close curly brackets
Q19. Let A = {2, 4, 6} and B = {6, 8, 12, 18}. Define a relation R from A to B by R= {(x, y): x divides y; x A, y B}. Express R as a set of ordered pairs.

Solution

R = {(2, 6), (2, 8), (2, 12), (2, 18), (4, 8), (4, 12), (6, 6), (6, 12), (6, 18)}
Q20. Find the domain of the function given by: .

Solution

f(x) is defined only when or when x -1, -2 So, Domain of f(x) = R – {-1, -2}
Q21. Let A = {1, 2, 3}, B = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10} f: A B be defined as f(x) = x + 5. Find the domain and range of the function.

Solution

We have, f(x) = x + 5 f(1) = 6, f(2) = 7, f(3) = 8 So, f = {(1, 6), (2, 7), (3, 8)} Domain of f = {1, 2, 3} Range of f  = {6, 7, 8}


Comments

Popular posts from this blog

10

Q1. 1) 780 2) 861 3) 820 4) 901 Solution Q2. Solution Let the given points be D(p, 0), E(r, s) and F(0, q) Since the points lie on the same line,  Slope of DE = Slope of EF                Slope of DE =  Slope of EF =  Q3. Without using distance formula, show that the points (-2, 1), (5, 3), (6, 7) and (- 4, 5) are not the vertices of a parallelogram. Solution Q4. Find the slope of line which passes through the point (5, 6) and the mid-point of line joining the points (4, 6) and (-3, 7). Solution Mid-point joining the line segment the points (4, 6) and (-3, 7) = Slope of line joining the points (5, 6) and Q5. If three points (3, 6), (-5, 7) and (x, 1) are collinear, find the value of x. Solution ...

15

Q1. Solution Q2. Solution         Class interval x f xf d=|x-mean| fd 0-10 5 5 25 22 110 10-20 15 8 120 12 96 20-30 25 15 375 2 30 30-40 35 16 560 8 128 40-50 45 6 270 18 108 total   50 1350   472 Class interval x f cf d=|x-median| fd 0-10 5 5 5 20 100 10-20 15 8 13 5 40 20-30 25 15 28 0 0 30-40 35 16 44 10 160 40-50 45 6 50 20 120 total   50     420 Q3. Solution Q4. Solution Q5. Solution Q6. Solution Q7. Solution Firm B shows greater variability. Q8. Solution Q9. Solution Q10. Solution Q11. Solution Q12. Solution Take Another Test

12

Q1. Show that the points (-2, 3 , 5 ) , ( 1, 2 , 3 ) and ( 7, 0 , -1 ) are collinear. Solution Q2. Find the co-ordinates of the point which divide the line segment joining the point (1,-2,3) and (3,4,-5) in the ratio 2 : 3 externally. Solution Q3. Find the ratio in which the line segment joining the points (5,9,11) and (7,11,-9) is divided by the YZ plane Solution Q4. Name the octant in which the following points lie : (i) (4,-2,-5) (ii) (-4,2,-5)(iii) (1,2,3) Solution (i) VIIIth Octant (ii) VIth Octant (iii) Ist Octant Q5. A point is in the YZ plane. What is the value of the x-coordinate? Solution Since the point lies in the YZ plane the value of x-cordinate is zero. Q6. Find the equation of the set of points which are equidistant from the points (1, 2, 3) and (3, 2, -1) Solution Q7. If the origin is the centroid of the triangle PQR with vertices P(2a,2,6) Q(-4,3b,-10) and R(8,14,2c), then find the values of a,b,c Solutio...