Question

(2√8+3√5-7√2)(√72-5√20-2√2)=rezolvati

Answer 1

$(2\sqrt{8}+3\sqrt{5}-7\sqrt{2})(\sqrt{72}-5\sqrt{20}-2\sqrt{2})= \\ (\sqrt{2^2*8}+\sqrt{3^{2}*5}-\sqrt{7^{2}*2})(\sqrt{72}-\sqrt{5^{2}*20}-\sqrt{2^{2}*2})= \\ (\sqrt{32}+\sqrt{45}-\sqrt{98})(\sqrt{72}- \sqrt{500}-\sqrt{8})= \\ (\sqrt{6,07900211657})( \sqrt{-279,017787183})$

Answer 2

$(2 \sqrt{8} +3 \sqrt{5} -7 \sqrt{2} )( \sqrt{72} -5 \sqrt{20} -2 \sqrt{2} )= \\ =(2 \cdot 2 \sqrt{2} +3 \sqrt{5} -7 \sqrt{2} )(6 \sqrt{2} -5 \cdot 2 \sqrt{5} -2 \sqrt{2} )= \\ =(4 \sqrt{2} +3 \sqrt{5} -7 \sqrt{2} )(6 \sqrt{2} -10 \sqrt{5} -2 \sqrt{2} )= \\ =(-3 \sqrt{2} +3 \sqrt{5} )(4 \sqrt{2} -10 \sqrt{5} )= \\ =-24+30 \sqrt{10} +12 \sqrt{10} -150=-174+42 \sqrt{10}$