Question

The image of the point $A(1,2)$ by the line mirror $y=x$ is the point $B$ and the image of $B$ by the line mirror $y=0$ is the point $(\alpha ,\beta )$, then?

• A. $\alpha =1,\beta =-2$
• B. $\alpha =0,\beta =0$
• C. $\alpha =2,\beta =-1$
• D. $\alpha =1,\beta =-1$

Answer 1

The correct option is C $\alpha =2,\beta =-1$

image of $A(1,2)$ w. r.t. $y=x$ is $B$

$\Rightarrow B=(2,1)$

and image of $B(2,1)$ $\omega \cdot r\cdot t,y=0$ is

(2,-1) i.e $x$ remains same but $y$ becmoes negative.

$\Rightarrow \alpha =2,\beta =-1$

option C is correct.