10.
36-12a+a2
=62-2(6)(a)+a2
=(6-a)2
12.
4+12n +9n2
=22+2(2)(3n)+(3n)2
=(2+3n)2
14.
25p2+60pq+36q2
=(5p)2+2(5p)(6q)+(6q)2
=(5p+6q)2
16.
16u2-72uv+81v2
=(4u)2-2(4u)(9v)+(9v)2
=(4u-9v)2
=[(2u)2-(3v)2]2
=[(2u+3v)(2u-3v)]2
=(2u+3v)2(2u-3v)2
18.
8-40 l +50 l2<---- l->L細階
=2(4-20 l + 25 l2)
=2((2)2-2(2)(5 l)+(5 l)2
=2(2-5 l )2
20.
80r2+40rs+5s2
=5(16r2+8rs+s2)
=5((4r)2+2(4r)(s)+s2)
=5(4r+s)2
22.
(c-d)2+4(c-d)+4
=(c-d)2+2(c-d)(2)+22
=[(c-d)+2]2
=(c-d+2)2
24.
4(x-y)2-4 z(x-y) + z2
= 22(x-y)2-2(2)(x-y)(z) +z2
=(2(x-y))2-2(2)(x-y)(z)+z2
=[(2(x-y))-z]2
=(2x-2y-z)2
26.
m4-18m2+81
=(m2)2-2(m2)(9)+92
=(m2-9)2
=(m2-32)2
=(m+3)2(m-3)2
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