Solveeit Logo

Question

Mathematics Question on Increasing and Decreasing Functions

The equation xlogx=2xx log x = 2 - x is satisfied by at least one value of xx lying between 11 and 22. The function f(x)=xlogxf(x) = x log x is an increasing function in [1,2][1,2] and g(x)=2xg (x)=2-x is a decreasing function in [1,2][1, 2] and the graphs represented by these functions intersect at a point in [1,2][1,2]

A

Statement-1 is true; Statement-2 is true; Statement-2 is a correct explanation for Statement-1.

B

Statement-1 is true; Statement-2 is true; Statement-2 is not correct explanation for Statement-1.

C

Statement-1 is false, Statement-2 is true.

D

Statement-1 is true, Statement-2 is false.

Answer

Statement-1 is true; Statement-2 is true; Statement-2 is a correct explanation for Statement-1.

Explanation

Solution

f(x)=xlogx,f(1)=0,f(2)=4f\left(x\right)=x\,log\,x,\,f\left(1\right) = 0,\,f\left(2\right) = 4
g(x)=2x,g(1)=1,g(2)=0g\left(x\right) = 2-x,\,g\left(1\right)=1,\,g\left(2\right) = 0
log10>log41>log4log 10 > log\,4 \Rightarrow 1 > log\,4
Thus statement -1 and 2 both are true and statement-2 is a correct explanation of statement 1.