Question 12***+Explain why the denominator becomes real when dividing by \\(c+di\\) using its conjugate.
Question 17****+Find all real \\(t\\) for which \\(\frac{2+ti}{t-i}\\) is real, with \\(t\neq0\\) not assumed.
Question 18*****A learner simplifies \\(\frac{1}{3+4i}\\) as \\(\frac13+\frac14i\\). Diagnose the error and find the reciprocal.