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  1. If x = 2 then the value of x3 + 27x2 + 243x + 631 is
    1. 1233
    2. 1211
    3. 1231
    4. 1321
Correct Option: A

Using Rule 8,
x3 + 27x2 + 243x + 631 = x3 + 3 . x2 × 9 + 3x.92 + 93 - 93 + 631
x3 + 27x2 + 243x + 631 = (x + 9)3 - 729 + 631
x3 + 27x2 + 243x + 631 = (2 + 9)3 – 98 { x = 2( Given ) }
x3 + 27x2 + 243x + 631 = 113 – 98 = 1331 – 98 = 1233



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