Thanks for your questions.  your questions was –

What will be the result of [10] – [3], if it is given that [x] = -x2.

Correct answer: a

Your question Explanation:
According to the given in question, [x] = -x2.
Substituting the value of x as x=10 in this equation, we get, [10] = -100
Now, substituting the value of x as x=3 in this equation, we get, [3] = -9
Now, substituting these values in [10] – [3] = (-100) – (-9) = -100 + 9 = -91
Hence, the correct answer is option a.

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