By making the substitution u=7^x and using part a, derive a hidden quadratic equation
7^(2x-1) +4×7^(x-1) -1/14 =0
and hence find all of the solutions to the above equation.
7^(2x-1) +4×7^(x-1) -1/14 =0
and hence find all of the solutions to the above equation.