Solve the following linear in equations in R.
Solve:-4x >30, when
(i) x ϵ R (ii) x ϵ Z (iii) x ϵ N
Now, -4x > 30
⇒x<−304=−152(i) If x ϵ R,then x<−152⇒xϵ(−∞,−152)(ii) If x ϵ Z,then x<−152⇒xϵ{...,−10,−9,−8}(iii)−4x>30⇒−x>304⇒x<−304As xϵN,so x can not be less than 1.∴ The solution set of the inequality −4x>30 is null set ϕ.