Question 22: \(\text { Value of expression } P=x^{5}-100 x^{4}+100 x^{3}-100 x^{2}+100 x-9 \text { at } x=99 \text { is: }\)
Since x=99, x+1=100
Then
\(P=x^{5}-100 x^{4}+100 x^{3}-100 x^{2}+100 x-9\)
\(=x^{5}-(x+1) x^{4}+(x+1) x^{3}-(x+1) x^{2}+(x+1) x-9 =x-9=99-9=90\)
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