Номер 121 помогите(7/12-8/15)2+4/5*(7/10-9/16)

Question

Номер 121 помогите
(7/12-8/15)2+4/5*(7/10-9/16)

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Answer 1

(7/12 - 8 /15)²+4/5(7/10-9/16)=9/80

1)   (7/12 - 8/15)²=(35/60 - 32/60)²=1225/3600 - 2 * 35/60 * 32/60 +1024/3600=2249/3600 - 1120/1800=2249/3600 - 2240/3600=9/3600=1/400

2)   7/10 - 9/16=56/80 - 45/80=11/80

3)   4/5*11/80=11/100

4)   1/400 + 11/100=1/400+44/400=45/400=9/80