Expression : $$x^{2}+\frac{1}{5}x+a^{2}$$
= $$[(x^2) + (2 * \frac{1}{10} * x) + (\frac{1}{10})^2] + a^2 - (\frac{1}{10})^2$$
= $$(x + \frac{1}{10})^2 + a^2 - (\frac{1}{10})^2$$
Now, for the above expression to be perfect square,
=> $$a^2 - (\frac{1}{10})^2 = 0$$
=> $$a^2 = (\frac{1}{10})^2$$
=> $$a = \frac{1}{10}$$
Create a FREE account and get: