1 19/81=100/81=(0,9)^(-2)
<span>0,9^x≥0,9^(-2) т.к. 0,9<1, то х≤-2 </span>
(x-(2-<span>√3)) (x-(2+<span>√3)) = 0; (x-2+<span>√3) (x-2-<span>√3) = 0; (x-2)^2-3 = 0; x^2-4x+4-3 = 0; <u>x^2-4x+1 = 0</u> </span></span></span></span>
(х - у)^4
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