方程log2[x 4]=[1 3]x的实数根有
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对数方程log2(x-1)=log4x化为log2(x-1)=½log2x2log2(x-1)=log2xlog2(x-1)²=log2x(x-1)²=X接下去解二次方程
log2^(4^x+4)=x+log2^[2^(x+1)-3]log2^(4^x+4)-log2^[2^(x+1)-3]=xlog2[(4^x+4)/(2^(x+1)-3)]=x(4^x+4)/(2^
设y=x2,则原方程变为:y2-y-6=0.分解因式,得(y-3)(y+2)=0,解得,y1=-2,y2=3,当y=-2时,x2=-2,x2+2=0,△=0-4×2<0,此方程无实数解;当y=3时,x
25x(13x4)=(25x4)x13运用了乘法交换律和乘法结合律.
log2【3^x-2】=log2【9^2-4】-3log2【3^x-2】=log2【77】-log2【8】log2【3^x-2】=log2【77/8】3^x-2=77/83^x=93/8x=log3【
log2(4^x+1)=x+log2[2^(x+3)-6]移项log2(4^x+1)-log2[2^(x+3)-6]=xlog2[(4^x+1)/(2^x×8-6)]=x即2^x=(4^x+1)/(2
5%x+(300-x)x4%=135x+(300-x)x4=13005x+1200-4x=1300x=1300-1200x=100
|logx|=|log(2x^2)|-2=|1+2logx|-2,设y=logx,方程变为|y|+2=|1+2y|,平方得y^2+4|y|+4=4y^2+4y+1,y>=0时3y^2=3,y=1;y
2.25x=90x=40
则有log2(2^x+1)=正负根号下2所以当log2(2^x+1)=根号下2时.2^x+1=2^根号下2时则x=log2[(2^根号下2时)-1]同理为log2(2^x+1)负根号下2时x=log2
2.8x4+5x=17.211.2+5x=17.25x=17.2-11.25x=6x=6÷5x=1.2
log2(2-x)=log2(x-1)+log(2)log2(2-x)=log2[2(x-1)]2-x=2x-2x=4/3带入检验,成立所以x=4/3
具体过程嘛.我写关键步成吗.log2(2((2^x)+1)))=2/log2((2^x)+1)log2(2)+log2((2^x)+1)=2/log2((2^x)+1)1+log2((2^x)+1)=
log2(x+14)-log2(x+6)=3-log2(x+2)∴log2[(x+14)/(x+6)]=log2[8/(x+2)]∴(x+14)/(x+6)=8/(x+2)且(x+14)/(x+6)>
由题意定义域2x+1>0x^2-2>0则x>√2而x^2-2=2x+1则x=3或x=-1则x=3
由x+4>0,x-1>0,x+8>0得x>1∵log2(x+4)+log2(x-1)=log2(2)+log2(x+8)∴log2(x+4)(x-1)=log2(x+8)*2,即(x+4)(x-1)=
4x+1.5x4=564x+6=564x=50x=25/2
4x+44=74+x3x=30x=10
1-2x-56=3-x4-2x+4x=3-1+562x=58x=58/2
(12.5+12.5%)x4=5x5x=50+0.5x=10+0.1x=10.1