Question

What is the condition for a function y = f(x) to be a monotonically increasing function

• A. $x_1>x_2\Rightarrow f\left(x_1\right)>f\left(x_2\right)$
• B. $x_1>x_2\Rightarrow f\left(x_1\right)=f\left(x_2\right)$
• C. $x_1>x_2\Rightarrow f\left(x_1\right)\ge f\left(x_2\right)$
• D. $x_1>x_2\Rightarrow f\left(x_1\right)<f\left(x_2\right)$

Answer 1

The correct option is C $x_1>x_2\Rightarrow f\left(x_1\right)\ge f\left(x_2\right)$

We know from the definition, that a monotonically increasing function is a function which increases or remains constant on increasing the values of x. That is y values or f(x) values increases or remains constant on increasing the x values. So if $x_1>x_2\Rightarrow f\left(x_1\right)\ge f\left(x_2\right)$

Text or Video solution : Text

Here, if the student gets option A as the correct answer, then student got confused with monotonically increasing and strictly increasing functions