be a real valued function.
Which one of the following statements is correct ?
f (x) is a strictly decreasing function in (0, x)
f(x) is a strictly increasing function in (0, x)
f(x) is neither increasing nor decreasing in (0, x).
f(x) is not decreasing in (0, x)
be a real valued function.
Which one of the following statements is correct ?
Select the correct answer using the code given below
1 only
2 only
Both 1 and 2
Neither 1 nor 2
Let f(x) = x2 + 2x – 5 and g(x) = 5x + 30
If h(x) = 5 f(x) – xg(x), then what is the derivative of h(x)
- 40
- 20
- 10
0
Let f(x) = x2 + 2x – 5 and g(x) = 5x + 30
What are the roots of the equation g[f(x)] = 0 ?
1, - 1
- 1, - 1
1, 1
0, 1
B.
- 1, - 1
D.
0, 1
Given f(x) = x2 + 2x – 5 and g(x) = 5x + 30
Now we have to find the value of g[f(x)], then we have to put the value of x as f(x) in function g(x).
Then, g[f(x)] = 5(x2 + 2x - 5) + 30 = 0 {it is given in the question that the value of g[f(x)] = 0}
now, it will become, g[f(x)] = 5x2 + 10x – 25 + 30 = 0
g[f(x)] = 5x2 + 10x + 5 = 0
g[f(x)] = 5{x2 + 2x + 1} = 0
g[f(x)] = 0 is possible only and only when the value of x2 + 2x + 1 = 0
then (x + 1 )2 = 0
it is possible only when x = - 1, - 1
hence, option B is correct.