不等式ax/(x-1)<1的解集為{x|x<1或x>2},則a的值是
熱心網(wǎng)友
解法一:ax/(x-1)=1,有兩個(gè)根x=1或x=2帶入方程,解得a=1/2解法二:ax/(x - 1) < 1[(a - 1)x +1]/(x - 1) < 0等價(jià)于[(a - 1)x + 1](x - 1) < 0(a-1)[x+1/(a-1)](x-1)2},即(x-1)(x-2)0所以a-1<0,且1/(a-1)=-2,也就a=1/2
熱心網(wǎng)友
ax/(x-1)=1,有兩個(gè)根x=1或x=2帶入方程,解得a=1/2
熱心網(wǎng)友
ax/(x-1)ax/(x-1)-1[(a-1)x+1]/(x-1)(a-1)[x+1/(a-1)]/(x-1)x2---a-10 (如果a1,其解為兩根之外.)[x+1/(a-1)](x-1)0有解x2對(duì)應(yīng)于方程[x+1/(a-1)](x-1)=0有解 x=1, x=2所以1-1/(a-1)=2---a-1-1=2(a-1)---a=0此時(shí)不等式成為01的一切實(shí)數(shù).故適合條件的a不存在.
熱心網(wǎng)友
等式ax/(x - 1) < 1的解集為{x|x2},則a的值是:解:ax/(x - 1) < 1—→[(a - 1)x - 1]/(x - 1) < 0①當(dāng)x < 1時(shí),x - 1,< 0所以(a - 1)x - 1 > 0,即(a - 1)x > 1由于x < 1,而(a - 1)x > 1,所以 a - 1 > 1,亦即 a > 2②當(dāng)x > 2時(shí),x - 1 > 0,所以(a - 1)x - 1 < 0,即(a - 1)x < 1由于x > 2,而(a - 1)x < 1,所以a - 1 < 1/2亦即 a < 3/2故a的取值為:a < 3/2 或 a > 2。