(a) \(\frac{1}{2}\) (2λ + 1)
log49(28) = log72 (7 x 22) = log72 7 + log72 22
= \(\frac{1}{2}\) log7 7 + \(\frac{2}{2}\) log7 2
\(\bigg[\)Using logan \(x\) = \(\frac{1}{n}\) loga x, logan (xm) = \(\frac{m}{n}\) loga x\(\bigg]\)
= \(\frac{1}{2}\) + λ = \(\frac{1}{2}\)(2λ + 1).