Question

Express in the roster form.

$D=\{x|x\in I$ and $x^2<10\}$

• A. $D=\{-2,-1,0,1,2\}$
• B. $D=\{-3,-2,-1,0,1,2,3\}$
• C. $D=\{-4,-3,-2,-1,0,1,2,3,4\}$
• D. None of these
  

Answer 1

Answer: (B)

$D=\{-3,-2,-1,0,1,2,3\}$

Since, $0^2=0<10$
$(\pm 1{)}^2=1<10$
$(\pm 2{)}^2=4<10$
$(\pm 3{)}^2=9<10$
$(\pm 4{)}^2=16>10$
$\therefore D=\{0,\pm 1,\pm 2,\pm 3\}$