F.2MATH

1. 36+12a+a^2
= 6^2 + 2(6)(a) + a^2
= (6+a)^2

2. 8m^2-8m+2
= 2(4m^2-4m+1)
= 2[(2m)^2-2(2)(1)+1^2]
= 2(2m-1)^2

3. a^2b^2-2abc+c^2
= (ab)^2 - 2(ab)(c) + c^2
= (ab-c)^2

4. 80r^2+40rs+5s^2
= 5(16r^2 + 8rs + s^2)
= 5[(4r)^2 + 2(4r)(s) + s^2]
= 5(4r+s)^2

5. 9-24(h-5k)+16(h-5k)^2
= 3^2 - 2(3)[4(h-5k)] + [4(h-5k)]^2
= [4(h-5k)-3]^2
= (4h-20k-3)^2

1.(a+9)^2
2.(4m-2)(2m-1)
3.?條題目好似唔是好correct.
4.(20+5s)(4+s)
5.Let (h-5k)be x .
=9-24x+16x^2
= (4b-3)^2