$180 = 2^2\cdot3^2\cdot5 $ $\left. \beginarrayc|c180 & 2\cr90 & 2 \cr45 & 3 \cr15 & 3 \cr5 & 5 \cr1\endarray \right.$ a) $5\sqrt180 + 3\sqrt27 - 2\sqrt32 = $ $5\sqrt2^2\cdot3^2\cdot5 + 3\sqrt3^3 - 2\sqrt2^5 = $ $5 \cdot 2 \cdot 3 \cdot \sqrt5 + 3\sqrt3^2 \cdot 3 - 2\sqrt2^2 (…)