2x²=5x-3=0
D=25+24=49
x1=(5-7)/4=-1/2
x2=(5+7)/4=3
6-5x²-7x=0
5x²+7x-6=0
D=49+120=169
x1=(-7-13)/10=-2
x2=(-7+13)/10=3/5
(2x²+5x-3)/(5x²+7x-6)≥0
+ _ + _ +
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-2 -1/2 3/5 3
x∈(-∞;-2) U [-1/2;3/5) U [3;∞)