Advertisements
Advertisements
Question
Let f: R → R be defined by f(x) = `{{:(2x",", x > 3),(x^2",", 1 < x ≤ 3),(3x",", x ≤ 1):}`. Then f(–1) + f(2) + f(4) is ______.
Options
9
14
5
None of these
Solution
Let f: R → R be defined by f(x) = `{{:(2x",", x > 3),(x^2",", 1 < x ≤ 3),(3x",", x ≤ 1):}`. Then f(–1) + f(2) + f(4) is 9.
Explanation:
Given that, f(x) = `{{:(2x",", x > 3),(x^2",", 1 < x ≤ 3),(3x",", x ≤ 1):}`
f(–1) = 3(–1) = –3 .....(Using f(x) = 3x)
f(2)= 22 = 4 ......(Using f(x) = x2)
f(4) = 2(4) = 8 ......(Using f(x) = 2x)
∴ f(–1) + f(2) + f(4) = 3 + 4 + 8 = 9
APPEARS IN
RELATED QUESTIONS
If the function f : R → R be given by f[x] = x2 + 2 and g : R → R be given by `g(x)=x/(x−1)` , x≠1, find fog and gof and hence find fog (2) and gof (−3).
Consider `f:R - {-4/3} -> R - {4/3}` given by f(x) = `(4x + 3)/(3x + 4)`. Show that f is bijective. Find the inverse of f and hence find `f^(-1) (0)` and X such that `f^(-1) (x) = 2`
Solve: sin(2 tan -1 x)=1
If f A→ A and A=R - `{8/5}` , show that the function `f (x) = (8x + 3)/(5x - 8)` is one-one onto. Hence,find `f^-1`.
Prove that the line 2x - 3y = 9 touches the conics y2 = -8x. Also, find the point of contact.
Let R be the equivalence relation in the set Z of integers given by R = {(a, b): 2 divides a – b}. Write the equivalence class [0]
If A = {1, 2, 3} and f, g are relations corresponding to the subset of A × A indicated against them, which of f, g is a function? Why?
f = {(1, 3), (2, 3), (3, 2)}
g = {(1, 2), (1, 3), (3, 1)}
Let f: R → R be defined by f(x) = sin x and g: R → R be defined by g(x) = x 2 , then f o g is ______.
Let f, g: R → R be defined by f(x) = 2x + 1 and g(x) = x2 – 2, ∀ x ∈ R, respectively. Then, find gof
Functions f , g: R → R are defined, respectively, by f(x) = x 2 + 3x + 1, g(x) = 2x – 3, find f o g
Functions f , g: R → R are defined, respectively, by f(x) = x 2 + 3x + 1, g(x) = 2x – 3, find g o f
Functions f , g: R → R are defined, respectively, by f(x) = x 2 + 3x + 1, g(x) = 2x – 3, find f o f
Functions f , g: R → R are defined, respectively, by f(x) = x 2 + 3x + 1, g(x) = 2x – 3, find g o g
If f : R → R and g : R → R defined by f(x) = 2x + 3 and g(x) = x2 + 7, then the value of x for which f(g(x)) = 25 is ____________.
Let f : R → R be given by f(x) = tan x. Then f-1(1) is ____________.
If f : `(1, infty) → (2, infty) "is given by f"("x") = "x" + 1/"x"`, then f-1 equals to ____________.
Let f(x) = x2 – x + 1, x ≥ `1/2`, then the solution of the equation f(x) = f-1(x) is ____________.