﻿ If , for all x Ïµ R, then : Kaysons Education

# If , For All x Ïµ R, Then

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## Question

### Solution

Correct option is

– 5 < a < 2

x2 + 2ax + 10 – 3a = + ive ∀ real values of x if dise 4a 2 – 4 (10 – 3 a) = – ive and sign of the first term i.e., 1 is + ive.

∴  a2 + 3a – 10 < 0

or (a + 5) (– 5) < 0

∴  – 5 < a < 2

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