Răspuns :
9ˣ⁺¹+9ˣ+9ˣ⁻¹= 91*3¹⁴
9ˣ*9+9ˣ+9ˣ*9⁻¹=9 1*9⁷
9ˣ (9+1+1/9= 91*9⁷
9ˣ*(10+1/9)= 91*9⁷
9ˣ (91/9+1/9)=91*9⁷
9ˣ * 91/9 = 91* 9⁷
9ˣ * 1/9 *91 = 91*9⁷
x-1=7
x=8
9ˣ*9+9ˣ+9ˣ*9⁻¹=9 1*9⁷
9ˣ (9+1+1/9= 91*9⁷
9ˣ*(10+1/9)= 91*9⁷
9ˣ (91/9+1/9)=91*9⁷
9ˣ * 91/9 = 91* 9⁷
9ˣ * 1/9 *91 = 91*9⁷
x-1=7
x=8