1)x1+x2=(1+√3+1-√3)/2=1
x1*x2=(1-3)/2=-1/2
x²-x-1/2=0
2x²-2x-1=0
2)<span>((a)-(bc/b-c))÷((b)-(ac/a-c))=(ab-ac-bc)/(b-c)*(a-c)/(ab-bc-ac)=(a-c)/(b-c)
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1) 420÷6=70 (тенге) - 1 великий мяч
2) 240÷8=30 (тенге) - 1 маленький мяч
( 1 + 2 ) × 3 + 4 × 5 = 29
Х - 8/15x = 4 1/5
15/15x - 8/15x = 21/5
7/15x = 21/5
x = 21/5 : 7/15
x = 21/5 * 15/7
x = 9
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