D=8^2- 7*4= 64-28=36 =6^2
X1=(-8-6)/2=-7
X2=(-8+6)/2=-1
Точка разрыва х=2, т к 2²=4, а 2+1=3
2а в кубе=8а
12а в квадрате=144а
8а+144а+18а=170а
287^2-287*48+239*713 = 287*(287-48) + 239*713 = 287 * 239 + 239*713 =
239*(287+713)=239*1000 = 239000
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73.4^2+73.4*17.2-90.6*63.4 = 73.4*(73.4 + 17.2) = 73.4 * 90.6 - 90.6 * 63.4 =
90.6*(73.4-63.4)=90.6*10=906