`7^x= 1/343` , VALUE OF x =

The following steps are involved in finding the value (7+x)^3 , when (7x)^3=343 . Arrange in sequential order. (A) (7+x)^3=(7+1)^3=8^3=512 (B) x^3=(343)/(7^3)=(7^3)/(7^3)=1 (C) rArrx=1 (D) (7x)^3=(343)/(7^3)=(7^3)/(7^3)=1

If 7^(log 7(x^(2)-4x + 5))=x - 1 , x may have values

1 7 49 343 (?)