Q.
If x∈R, then the maximum and minimum values of x2+14x+9x2+2x+3 are
see full answer
High-Paying Jobs That Even AI Can’t Replace — Through JEE/NEET
🎯 Hear from the experts why preparing for JEE/NEET today sets you up for future-proof, high-income careers tomorrow.
An Intiative by Sri Chaitanya
a
3,1
b
0, −∞
c
4, −5
d
∞, −∞
answer is C.
(Unlock A.I Detailed Solution for FREE)
Detailed Solution
Let the given condition x2+14x+9x2+2x+3 =m, then ⇒(1−m)x2+(14−2m)x+ (9−3m)=0But x∈R, therefore, (14−2m)2−4.(1−m)(9−3m) ≥0 (∵ if x is real ⇒b2−4ac≥0 )⇒ 4m2−56m+196−12m2+48m−36≥0 ⇒ −8m2−8m+160 ≥0 ⇒ m2+m−20 ≤ 0 ⇒ (m+5) (m−4) ≤0 ⇒-5⩽m≤4 ∴ maximum value = 4and minimum value = −5
Watch 3-min video & get full concept clarity