Question 1
Among the four statements on integers below,
- “If $a\lt b$ then $a^2\lt b^2$”;
- “$a^2\gt 0$ is always true”;
- “$-a\lt 0$ is always true”;
- “If $ac^2\lt bc^2$ then $a\lt b$”,
how many of them are correct?
- “If $a\lt b$ then $a^2\lt b^2$”;
- “$a^2\gt 0$ is always true”;
- “$-a\lt 0$ is always true”;
- “If $ac^2\lt bc^2$ then $a\lt b$”,
how many of them are correct?