探究并计算(大胆实践,你一定能探索成功!)观察后面等式:11×2=1-12,12×3=12-13,13×4=13-14,将前面三个等式两边分别相加得:11×2+12×3+13×4=1-12+12-13+13-14=1-14=34.(1)猜-数学
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