1 x²-7x+12=0 x=3;4 x²-x+2=0 D=1-8<0 выраж. больше нуля<br>(x-3)(x-4)≤0 -----------3----------4----------- x∈[3;4]
+ - +
2/ x²-3x-4=0 x= 4; -1 x²-2x-15=0 x=5;-3
(x-4)(x+1)(x-5)(x+3)≤0
----- -3-------- -1 ------- 4-------- 5--------- x∈[-3;-1]∪[4;5]
+ - + - +
3. x²-x-12=0 x=4; -3 x≠1 (x-4)(x+3)/(x-1)>0
------------------- -3------------1----------- 4----------------- x∈(-3;1)∪(4;∞)
- + - +
4. x²-4x-12=0 x=6;-2 (x-6)(x+2)/(x-2)<0 x≠2<br>
----------- -2 ---------- 2--------------- 6------------------- x∈(-∞;-2)∪(2;6)
- + - +
5. x²+3x-10=0 x=-5;2 x²+x-2=0 x=-2;1
(x+5)(x-2)/(x+2)(x-1)≤0 x≠ -2;1
--------------- -5----------- -2------------- 1------------- 2-------------
+ - + - +
x∈[-5; -2)∪(1;2]
6. (x-4)(x+1)/(x+3)(x-2) ≥0 x≠-3;2
∨ ∨
--------- -3-------- -1----------2---------- 4--------------
+ - + - +
x∈(-∞;-3)∪[-1;2)∪[4;∞)