1.(-1又1/2)*(-1又1/3)*(-1又1/4)*...(-1又1/2012) 2.已知x+1的绝对值=4,(y+2)的2次方=9,求x+y的值

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1.(-1又1/2)*(-1又1/3)*(-1又1/4)*...(-1又1/2012) 2.已知x+1的绝对值=4,(y+2)的2次方=9,求x+y的值

1.(-1又1/2)*(-1又1/3)*(-1又1/4)*...(-1又1/2012) 2.已知x+1的绝对值=4,(y+2)的2次方=9,求x+y的值
1.(-1又1/2)*(-1又1/3)*(-1又1/4)*...(-1又1/2012) 2.已知x+1的绝对值=4,(y+2)的2次方=9,求x+y的值

1.(-1又1/2)*(-1又1/3)*(-1又1/4)*...(-1又1/2012) 2.已知x+1的绝对值=4,(y+2)的2次方=9,求x+y的值
1、原式=(-3/2)*(-4/3)*(-5.4)*……*(-2013/2012)=-2013/2
(原式中共有奇数个因子,所以得数符号为负
2、x=3或-5
y=1或-3
则x+y=4或0或-4或-8