Datrys sqrt{2/5}*sqrt{50}-sqrt{45}

$$\sqrt { \frac { 2 } { 5 } } \times \sqrt { 50 } - \sqrt { 45 }$$

Enrhifo

$$-\sqrt{5}\approx -2.236067977$$

Camau Ateb

Ailysgrifennu ail isradd y rhaniad \sqrt{\frac{2}{5}} fel rhaniad ail israddau \frac{\sqrt{2}}{\sqrt{5}}.

$$\frac{\sqrt{2}}{\sqrt{5}}\sqrt{50}-\sqrt{45}$$

Mae'n rhesymoli enwadur \frac{\sqrt{2}}{\sqrt{5}} drwy luosi'r rhifiadur a'r enwadur â \sqrt{5}.

$$\frac{\sqrt{2}\sqrt{5}}{\left(\sqrt{5}\right)^{2}}\sqrt{50}-\sqrt{45}$$

Sgwâr \sqrt{5} yw 5.

$$\frac{\sqrt{2}\sqrt{5}}{5}\sqrt{50}-\sqrt{45}$$

I luosi \sqrt{2} a \sqrt{5}, dylid lluosi'r rhifau dan yr ail isradd.

$$\frac{\sqrt{10}}{5}\sqrt{50}-\sqrt{45}$$

Ffactora 50=5^{2}\times 2. Ailysgrifennu ail isradd y lluoswm \sqrt{5^{2}\times 2} fel lluoswm ail israddau \sqrt{5^{2}}\sqrt{2}. Cymryd isradd 5^{2}.

$$\frac{\sqrt{10}}{5}\times 5\sqrt{2}-\sqrt{45}$$

Canslo 5 a 5.

$$\sqrt{10}\sqrt{2}-\sqrt{45}$$

Ffactora 10=2\times 5. Ailysgrifennu ail isradd y lluoswm \sqrt{2\times 5} fel lluoswm ail israddau \sqrt{2}\sqrt{5}.

$$\sqrt{2}\sqrt{5}\sqrt{2}-\sqrt{45}$$

Lluosi \sqrt{2} a \sqrt{2} i gael 2.

$$2\sqrt{5}-\sqrt{45}$$

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}.

$$2\sqrt{5}-3\sqrt{5}$$

Cyfuno 2\sqrt{5} a -3\sqrt{5} i gael -\sqrt{5}.

$$-\sqrt{5}$$