1.234²+0.766²+2.468乘以0.766

1.234²+0.766²+2.468乘以0.766
1.234²+0.766²+2.468乘以0.766

1.234²+0.766²+2.468乘以0.766
1.234²＋0.766²＋2.468×0.766
＝1.234²＋2×1.234×0.766＋0.766²
＝(1.234＋0.766)²
＝2²
＝4

1.234²+0.766²+2.468乘以0.766
=1.234²+0.766²+2x1.234x0.766
=(1.234+0.766)平方
=2平方
=4

没看出来是完全平方和吗？
1.234²+0.766²+2.468乘以0.766
=(1.234+0.766)^2
=4