Réitigh (2sqrt{7}+3sqrt{2})*(5-2sqrt{2}

$$( 2 \sqrt { 7 } + 3 \sqrt { 2 } ) \cdot ( 5 - 2 \sqrt { 2 }$$

Luacháil

$$10\sqrt{7}+15\sqrt{2}-4\sqrt{14}-12\approx 20.704086999$$

Céimeanna Réitigh

Cuir an t-airí dáileacháin i bhfeidhm trí gach téarma de 2\sqrt{7}+3\sqrt{2} a iolrú faoi gach téarma de 5-2\sqrt{2}.

$$10\sqrt{7}-4\sqrt{7}\sqrt{2}+15\sqrt{2}-6\left(\sqrt{2}\right)^{2}$$

Iolraigh na huimhreacha faoin bhfréamh cearnach chun \sqrt{7} agus \sqrt{2} a iolrú.

$$10\sqrt{7}-4\sqrt{14}+15\sqrt{2}-6\left(\sqrt{2}\right)^{2}$$

Is é 2 uimhir chearnach \sqrt{2}.

$$10\sqrt{7}-4\sqrt{14}+15\sqrt{2}-6\times 2$$

Méadaigh -6 agus 2 chun -12 a fháil.

$$10\sqrt{7}-4\sqrt{14}+15\sqrt{2}-12$$

Fachtóirigh

$$10 \sqrt{7} + 15 \sqrt{2} - 4 \sqrt{14} - 12 = 20.704086999$$