Question

Choose the correct option:
i. $y=4a$, is a linear function.
ii. $y=a{x}^2-bx+c,(a=0)$, is a linear function with positive slope.
iii. $y=x$, is an identity function.
iv. $y=3x^2-1$, is a quadratic function.

• A. i and ii
• B. iii and iv
• C. i, ii and iii
• D. ii and iv

Answer 1

The correct option is B iii and iv

i. $y=4a$, is a constant function as $4a$ is a constant value.
ii. $y=a{x}^2-bx+c,(a=0)$, is a linear function as $a=0\Rightarrow y=-bx+c$, also comparing this equation with the equation of line i.e. $y=mx+c$, we get the slope as $m=-b$, which is negative.
iii. $y=x$ is an identity function.
iv. $y=3x^2-1$ is a quadratic function as the degree of the given polynomial function is $2$.