来自牛杰的问题
初三2道计算题1.(15根号1/48-6根号27)/2根号32.根号2*X^2-(根号2+2)=0
初三2道计算题
1.(15根号1/48-6根号27)/2根号3
2.根号2*X^2-(根号2+2)=0
1回答
2020-04-14 21:35
初三2道计算题1.(15根号1/48-6根号27)/2根号32.根号2*X^2-(根号2+2)=0
初三2道计算题
1.(15根号1/48-6根号27)/2根号3
2.根号2*X^2-(根号2+2)=0
1.(15*(1/48)^0.5-6*(27)^0.5)/(2*3^0.5)
=(15*(1/3^0.5)/4-6*3*3^0.5)/(2*3^0.5)
=(3^0.5)*(15*/3/4-18)/(2*3^0.5)
=(5/4-18)/2
=(5-32)/4/2
=-27/8
2.2^0.5*X^2-(2^0.5+2)=0
2^0.5*X^2=(2^0.5+2)
X^2=(2^0.5+2)/2^0.5
=1+2^0.5
X1=(1+2^0.5)^0.5
X2=-(1+2^0.5)^0.5