Задача 23934 70^2-6*70+9 / 70^2-9 : 10*70-30 /...

u525119831

19.02.2018

70^2-6*70+9 / 70^2-9 : 10*70-30 / 70^2+3*70

SOVA

19.02.2018

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В написании условия нужны скобки:
(70^2–6·70+9) / (70^2–9) : (10·70–30) / (70^2+3·70)

1)70^2–6·70+9=(70-3)^2=67^2
2)70^2–9=(70-3)*(70+3)=67*73

3)67^2/(67*73)=67/73;

4)10·70–30=700-30=670
5) 70^2+3·70=70*(70+3)=70*73

6)670/(70*73)=67/(70*73)

7)

(70^2–6·70+9) / (70^2–9) : (10·70–30) / (70^2+3·70) =

=(67/73):(67/(70*73))=(67/73)*((70*73)/67)=70