For a, b ∈ R, define a * b = aa + b, where a + b ≠ 0. If a * b = 5, then the value of b * a is
5
- 5
4
- 4
Let A = {x, y, z} and B = {a, b, c, d}. Which one of the following is not a relation from A to B ?
{(x, a), (x, c)}
{(y, c), (y, d)}
{(z, a), (z, d)}
{(z, b), (y, b), (a, d)}
If f(x) = x2 - 1 and g(x) = (x + 1)2, then (gof) (x) is
(x + 1)4 - 1
x4 - 1
x4
(x + 1)4
If the function f : [1, ∞) → [1, ∞) is defined by f(x) = 2x(x - 1), then f-1(x) is
12xx - 1
121 - 1 + 4log2x
121 + 4log2x
121 + 1 + 4log2x
If n(A) = 8 and nA ∩ B = 2, then nA ∩ B' ∩ A is equal to
2
6
8
If f(x) = sinx + cosx, x ∈ - ∞, ∞ and g(x) = x2, x ∈ - ∞, ∞, then (fog)(x) is equal to
1
0
sin2x + cosx2
sinx2 + cosx2
D.
fx = sinx + cosx, x ∈ - ∞, ∞and gx = x2, x ∈ - ∞, ∞ fog(x) = fgx = fx2 = sinx2 + cosx2
If n(A) = 5 and n(B) = 7, then the number of relations on A x B is
235
249
225
235 × 35
Let ϕx = bx - ab - a + ax - ba - b, where x ∈ R and a and b are fixed real numbers with a ≠ b. Then, ϕa + b is equal to
ϕab
ϕ- ab
ϕa + ϕb
ϕa - b
The range of the function f(x) = x2 + 8x2 + 4, x ∈ R is
- 1, 32
(1, 2]
(1, 2)
[1, 2]
If n(A) = 1000, n(B) = 500 and if n(A ∩ B) ≥1 and nA ∪ B = p, then
500 ≤ p ≤ 1000
1001 ≤ p ≤ 1498
1000 ≤ p ≤ 1498
1000 ≤ p ≤ 1499