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计算或化简(1)(2a2-3b+4c)(2a2+3b-4c)(2)(2x+3y)2(2x-3y)2(3)(5a-3b)(5a+3b)(25a2-9b2)(4)−12006−8(π−2)0+(−12)−2×2;(5)(−12)2+(119)0+(−5)3÷(−5)2(6)(1−122)(1−132)(1−142)…(1

题目详情
计算或化简
(1)(2a2-3b+4c)(2a2+3b-4c)
(2)(2x+3y)2(2x-3y)2
(3)(5a-3b)(5a+3b)(25a2-9b2
(4)12006−8(π−2)0+(−
1
2
)−2×2;
(5)(−
1
2
)2+(
1
19
)0+(−5)(−5)2
(6)(1−
1
22
)(1−
1
32
)(1−
1
42
)…(1−
1
1002
).
▼优质解答
答案和解析
(1)原式=[2a2-(3b-4c)][2a2+(3b-4c)],
=4a2-(3b-4c)2
=4a2-9b2+24bc-16c2

(2)原式=[(2x+3y)(2x-3y)]2
=(4x2-9y22
=16x4-72x2y2+81y4

(3)原式=(25a2-9b2)•(25a2-9b2),
=(25a2-9b22
=125a4-450a2b2+81b4

(4)原式=-1-8×1+4×2=-1;

(5)原式=
1
4
+1+(-5)1
=
1
4
+1-5,
=-
15
4


(6)原式=(1+
1
2
)(1-
1
2
)(1+
1
3
)(1-
1
3
)…(1+
1
100
)(1-
1
100
),
=
3
2
×
1
2
×
4
3
×
2
3
×
5
4
×
3
4
…×
100
99
×
98
100
×
101
100
×
99
100

=
1
2
×
101
100

=
101
200