Straight away we can see that x = 0 works. The product goes to zero in this case. When x takes values -3, -5 or -8, the product will go to zero and the inequality holds good.Now, let us substitute some other values.
When x = 1 => Product = 1 * 4 * 6 * 9 = 216 < 250 So, x = 1 holds good.
When x = 2 => The product is clearly greater than 250.
>So, thus far, we have seen that for x = 0, -3, -5, -8 or 1; the above inequality holds good.
There are 4 terms in this product. If all 4 are positive or all 4 are negative, the product will be positive. If exactly one term is positive or exactly one term is negative, the product will be negative.
Whenever the product is negative, the inequality will hold good. So, let us find the values of x for which the product will be negative.
x = -1 or -2, the product is negative, so the inequality will hold good.
Let us think of other values of x for which the product is negative. For the product to be negative, either 1 or 3 of the four terms should be negative.
When x is -6 or -7, three of the terms are negative and the product is negative.
So, for x = 0, 1, -3, -5, -8, -1, -2, -6 or -7 this holds good. We have seen 9 values thus far.
In ascending order, the values are -8, -7, -6, -5, -3, -2, -1, 0, 1
The value in between that we have thus far not verified is -4. Let us try -4 as well. In this case the product is -4 * -1 * 1 * 7 < 250
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