Возводишь все в квадрат и решаешь
7х+1-2x+7=3x+18
x=5
<span> x^2+1/ x+1 * x^2+2x+1/ 1-x^4 = (x^2 + 1)(x+1)^2 / (x+1)(1-x^2)(1+x^2) = (x+1)/(1-x)(1+x) = 1/(1-x) </span>
X = 1,21(32)
100x = 121,(32)
10000x = 12132,(32)
9900x = 12011
12011-9900 = 2111
x= 1 целая 2111/9900
x² +44=165
х²=165-44
х²=121
х=11
Значение х=11............................................................................
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