1) 598*985=589030
2) 597*985= 588045
3) 589030-588045= 985
4) 985+597015=598000
Функция:у=2/(2+х)
1)если у равен 5,то
2/(2+х)=5
2+х=2:5
2+х=0.4
х=-1.6
4x²=7x-3 D=b²-4ac
4x²-7x+3=0
a=4 b=-7 c=3
D=(-7)²-4×4×3=49-48=1 √D=1
x₁=7-1/2×4=6/8=3/4
x₂=7+1/2×4=8/8=1
2x²+5=-7x
2x²+7x+5=0
a=2 b=7 c=5
D=7²-4×2×5=49-40=9 √D=3
x₁=-7-3/2×2=-10/4=-5/2
x₂=-7+3/2×2=-4/4=-1
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