255
а)(x+1,2)(x+1 1/3)≥0
x=-1,2 x=-1 1/3
+ _ +
-----------[-1 1/3]--------[-1,2]------------
x∈(-∞;-1 1/3] U [-1,2;∞)
б)(x+1/6)(x+3/7)(x-1/8)<0<br>x=-1/6 x=-3/7 x=1/8
_ + _ +
--------------(-3/7)----------(-1/6)----------(1/8)------------
x∈(-∞;-3/7) U (-1/6;1/8)
в)x(x-4)(x-4,2)(x-4 1/3)<0<br>x=0 x=4 x=4,2 x=4 1/3
+ _ + _ +
-----------(0)--------------(4)------------(4,2)-------------(4 1/3)------------
x∈(0;4) U (4,2;4 1/3)
259
а)x(x+1)(7-x)(7+x)<0<br>x=0 x=-1 x=7 x=-7
_ + _ + _
-------------(-7)-------------(-1)------------(0)-----------(7)-------------------
x∈(-∞;-7) U (-1;0) U (7;∞)
б)(x-1)(x+1)(x²+1)(x²+11)>0
x²+1 и x²+11 больше 0 при любом х⇒((x-1)(x+1)>0
x=1 x=-1
+ _ +
-----------(-1)-------------(1)-------------
x∈(-∞;-1 ) U (1∞)
д)x²(x-3)(x²+7)≤0
x²+7 больше 0 при любом х⇒x²(x-3)≤0
x=0 x=3
_ _ +
--------------[0]------------------[3]--------------
x∈(-∞;3]
е)(x²-6x+5)(x+8)>0
x²-6x+5=0
x1+x2=6 U x1*x2=5⇒x1=1 U x2=5
x+8=0⇒x=-8
_ + _ +
----------------(-8)--------------(1)---------(5)-----------------
x∈(-8;1) U (5;∞)