Question

Let 1 be an open interval contained in thedomain of a real function $f^{\prime }$, then $f\left(x\right)$ is called strictly decreasing function in 1 if

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

Answer 1

Answer: (B)

$x_1<x_2$ in $I=f\left(x_1\right)>f\left(x_2\right)$

Basic defination of decreasing function
If $x_1>x_2$ & $f\left(x_1\right)<f\left(x_2\right)$ than function is decreasing.