??????? ???????? ??????? ????????? ???
f(x)=ax�+bx+c
??????? ???????????? ?????????????? ????? ??????? ???
D=b�-4ac
-x�+2x-15=0
a=-1, b=2, c=-15
??????? ???????????? ???????????? 0-??? ?? ??? ????? ??????? ??? D>0
x? ,x? ????? 2 ???????
??????? ???????????? ???????????? 0-??? ?????? ??? ????? ??????? ??? D=0
x?=x? ?????? ??? 1 ???????
??????? ???????????? ???????????? 0-??? ???? ??? ????? ??????? ??? D<0
????? ???? ??????? ???? ? ??? ??????????.
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?>0 ??? ????????? ????? ?????? ?????
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?<0 ??? ????????? ????? ?????? ?????
D>0 ??? ??????? X ?????????? ????? ?????? ?????? ???
????
D<0 ??? ??????? X ?????????? ????? ?????? ?????? ???
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1. ?? ????? ???????? ?????????? ??????.
2. ??????? ???????????? ????? ??????? ????
3. ??????? ??? ?????, ? ????????????? ???????? ?????????? ????????? ??????? ?????
4. ? ?????????? ???? ????? ??????? + ?????? , ???? ????? ??????? - ???????? ??? ??? ??????
????????? ?????? ?? ????? ?????? ??? ?????? ????? ????? ?????? ????? ???
????? ????? ?????? ?????
????????? ?????? ?? ????? ?????? ????????? ?????? ????? ????? ?????? ????? ???
????? ????? ?????? ?????
??????????? ???????? ????? ?????? ?????? ???
????? ?????? ?????.
ax�+bx+c=0 ??????? ???????????? ??????? ????? ??????? ????? ???
x?,?=(-b�?D)/2a
?????????? ??????? ???????????? ????? ??????? ?????? ????? ???
x�+px+q=0
x?+x?=-p
x?*x?=q
x�+3x+2=0 ???????????? ???? x?, x? ??? x?+x?=?, x?*x?=?
x?+x?=-3
x?*x?=2
x�+2x-15=0 ???????????? ??????? ???
(3; -5)
x�-3x+2<0 ???????????? ??????? ???
x?: ]1;2[