Datrys sqrt{5}+2sqrt{45}-3sqrt{125}=-8sqrt{5}

$$\sqrt { 5 } + 2 \sqrt { 45 } - 3 \sqrt { 125 } = - 8 \sqrt { 5 }$$

Gwireddu

Camau Ateb

Ffactora 45=3^{2}\times 5. Ailysgrifennu ail isradd y lluoswm \sqrt{3^{2}\times 5} fel lluoswm ail israddau \sqrt{3^{2}}\sqrt{5}. Cymryd isradd 3^{2}.

$$\sqrt{5}+2\times 3\sqrt{5}-3\sqrt{125}=-8\sqrt{5}$$

Lluosi 2 a 3 i gael 6.

$$\sqrt{5}+6\sqrt{5}-3\sqrt{125}=-8\sqrt{5}$$

Cyfuno \sqrt{5} a 6\sqrt{5} i gael 7\sqrt{5}.

$$7\sqrt{5}-3\sqrt{125}=-8\sqrt{5}$$

Ffactora 125=5^{2}\times 5. Ailysgrifennu ail isradd y lluoswm \sqrt{5^{2}\times 5} fel lluoswm ail israddau \sqrt{5^{2}}\sqrt{5}. Cymryd isradd 5^{2}.

$$7\sqrt{5}-3\times 5\sqrt{5}=-8\sqrt{5}$$

Lluosi -3 a 5 i gael -15.

$$7\sqrt{5}-15\sqrt{5}=-8\sqrt{5}$$

Cyfuno 7\sqrt{5} a -15\sqrt{5} i gael -8\sqrt{5}.

$$-8\sqrt{5}=-8\sqrt{5}$$

Ychwanegu 8\sqrt{5} at y ddwy ochr.

$$-8\sqrt{5}+8\sqrt{5}=0$$

Cyfuno -8\sqrt{5} a 8\sqrt{5} i gael 0.

$$0=0$$

Cymharu 0 gyda 0.

$$\text{true}$$