直接写得数．﹣=+=+=+=﹣=﹣=﹣=+= 1﹣=﹣=．
计算下面各题．+﹣+++﹣﹣（+）
﹣=+=﹣=﹣=+=﹣= 1﹣=﹣=﹣=+=
+++．
递等式计算+=+=﹣=﹣= 1﹣=+﹣= 1﹣+．
﹣
=
+
=
+
=
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=
﹣
=
﹣
=
=
+
=
=
﹣
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+
﹣
+
+
+
﹣
﹣（
+
）
﹣
=
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=
﹣
=
﹣
=
+
=
﹣
= 1﹣
=
﹣
﹣
=
+
=
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+
+
．
+
=
+
=
﹣
﹣
=
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+
﹣
=
+
．
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