探索發(fā)現(xiàn):
①當(dāng)a、b取不同數(shù)值時(shí),計(jì)算代數(shù)式a2-b2與代數(shù)式(a+b)(a-b)的值,請(qǐng)同學(xué)們將正確結(jié)果填入如表:
a、b的取值 |
當(dāng)a=3,b=2時(shí) |
當(dāng)a=-5,b=1時(shí) |
當(dāng)a=-2,b=-5時(shí) |
a2-b2 |
5 5
|
24 24
|
-21 -21
|
(a+b)(a-b) |
5 5
|
24 24
|
-21 -21
|
②根據(jù)上表計(jì)算,對(duì)于任意給a、b各取一個(gè)數(shù)值計(jì)算,a
2-b
2與代數(shù)式(a+b)(a-b)的值時(shí),蘊(yùn)含著一個(gè)規(guī)律,寫出你的發(fā)現(xiàn):
a2-b2=(a+b)(a-b)
a2-b2=(a+b)(a-b)
.
③用你發(fā)現(xiàn)的規(guī)律計(jì)算:2023
2-2022
2.