Question 35

Mathematics Linear and Quadratic Equations Hard

If x<sup>2</sup> + 2ax + 10 - 3a &gt; 0 for all x&nbsp;&isin; R, then

(A) - 5 &lt; a &lt; 2
(B) a &lt; -5
(C) a &gt; 5
(D) 2 &lt; a &lt; 5
View Dynamic Solution & Explanation
Correct Solution: Option A

Step-by-step Solution:

Given equation: \[ x^2 + 2ax + 10 - 3a > 0 \] According to the given condition, we have: \[ 4a^2 - 4(10 - 3a) < 0 \] \[ \Rightarrow a^2 + 3a - 10 < 0 \] \[ \Rightarrow (a + 5)(a - 2) < 0 \] \[ \Rightarrow -5 < a < 2 \]