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 $(Î\pm ,β)$, then :

• A. $Î\pm =1,β=−2$
• B. $Î\pm =0,β=0$
• C. $Î\pm =2,β=−1$
• D. none of these

Answer 1

Answer: (C)

Image of $A(1,2)$ in line mirror $y=x$ is $(2,1)$
Image of $B(2,1)$ in $y=0(x−$ axes $)$ is $(2,−1)$
Hence, $Î\pm =2,β=−1$