The solution set of the inequality
√6−x(5x2−7.2x+3.9−25√2)≥0 can be given by (−a,bc), then c - b =
xϵ(−∞,15)
First of all we must have
6−x≥0 ∴x≤6
Also 5x2−7.2x+3.9−5212≥0
⇒x2−7210x+3910≥52i.e.,2510
⇒5x2−36x+7≥0⇒(x−7)(5x−1)≥0
⇒x≤15,x≥7(Rejected as x≤6)
∴x≤15⇒xϵ(−∞,15)