A little problem

there was once a question in my exam which was ... please neglect those marks :P and we had to find the integral positive values which the parameter "a" can take , here b belongs to all real number ( it can be anything ) ! , and it is given that the ques in pic is non-decreasing for x belong to R , i got (after simplification ) :) he agreed o it :) and then said the answer was 1 and 2 but i marked only 1 since b^2 has to positive , and 1/4 is itself positive :P i said that if the co-efficient of b was zero , it will always be positive but he marked me wrong in the test can you tell why my approach is wrong ?

Easy Math Editor

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`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
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Comments

oh ! sorry i missed the equality! :P

A Former Brilliant Member - 4 years, 5 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$