问题
填空题
用平方差公式计算:49.8×50.2=(______)2-(______)2=______.
答案
49.8×50.2
=(50-0.2)×(50-0.2)
=502-0.22
=2500-0.04
=2499.96,
故答案为:50-0.2,50+0.2,2499.96.
用平方差公式计算:49.8×50.2=(______)2-(______)2=______.
49.8×50.2
=(50-0.2)×(50-0.2)
=502-0.22
=2500-0.04
=2499.96,
故答案为:50-0.2,50+0.2,2499.96.