b12+b5/b11+b4=4
q=?
b12=b1q^11
b5=b1q^4
b11=b1q^10
b4=b1q^3
b1(q^11+q^4)/b1(q^10+q^3)=4
q^11+q^4/q^10+q^3=4
q(q^10+q^3)/(q^10+q^3)=4
q=4
Ответ q=4
2х + 8 + 9х + ( - 18 ) + ( - 54 ) + 6х = 1
2х + 9х + 6x + 8 - 18 - 54 = 1
17х - 64 = 1
17х = 1 + 64
17х = 65
х = 65 / 17
х = 3,9
Ответ : 3,9
7 8\10:316=78\10*1\316=39\1580
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