Question

(1) tính

a) \(\sqrt{3}+2\sqrt{12}+4\sqrt{75}-\sqrt{300}\)

b) \(2\sqrt{20}+\sqrt{\left(1-\sqrt{5}\right)^2}-\dfrac{20}{\sqrt{5}+1}\)

c) \(\dfrac{6}{\sqrt{13}-1}+\dfrac{6}{\sqrt{13}+1}\)

d) \(\sin^238^0+\cot23^0+\sin^252^0-\tan67^0\)

giúp mk vs ạ mai mk hc rồi

Answer 1

\(a,=\sqrt{3}+4\sqrt{3}+20\sqrt{3}-10\sqrt{3}=15\sqrt{3}\\ b,=4\sqrt{5}+\sqrt{5}-1-\dfrac{20\left(\sqrt{5}-1\right)}{4}\\ =5\sqrt{5}-1-5\sqrt{5}+5=4\\ c,=\dfrac{6\sqrt{13}+6+6\sqrt{13}-6}{\left(\sqrt{13}-1\right)\left(\sqrt{13}+1\right)}=\dfrac{12\sqrt{13}}{12}=\sqrt{13}\\ d,=\left(\sin^238^0+\cos^238^0\right)+\left(\tan67^0-\tan67^0\right)=1+0=1\)