八年级下册数学运用公式法测试题
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八年级下册数学运用公式法测试题
![八年级下册数学运用公式法测试题](/uploads/image/z/3409039-55-9.jpg?t=%E5%85%AB%E5%B9%B4%E7%BA%A7%E4%B8%8B%E5%86%8C%E6%95%B0%E5%AD%A6%E8%BF%90%E7%94%A8%E5%85%AC%E5%BC%8F%E6%B3%95%E6%B5%8B%E8%AF%95%E9%A2%98)
49(a-b)" -16(a+b)"
=[7(a-b)+4(a+b)][7(a-b)-4(a+b)]
=(11a-3b)(3a-11b)
(2x+y)" - (x+2y)"
=(2x+y-x-2y)(2x+y+x+2y)
=(x-y)(3x+3y)
=3(x-y)(x+y)
(x"+y")" -x"y"
=(x"+y"+xy)(x"+y"-xy)
3ax"-3ay""
=3a(x"-y"")
=3a(x-y")(x+y")
P""-1
=(P"-1)(P"+1)
=(P-1)(P+1)(P"+1)
=[7(a-b)+4(a+b)][7(a-b)-4(a+b)]
=(11a-3b)(3a-11b)
(2x+y)" - (x+2y)"
=(2x+y-x-2y)(2x+y+x+2y)
=(x-y)(3x+3y)
=3(x-y)(x+y)
(x"+y")" -x"y"
=(x"+y"+xy)(x"+y"-xy)
3ax"-3ay""
=3a(x"-y"")
=3a(x-y")(x+y")
P""-1
=(P"-1)(P"+1)
=(P-1)(P+1)(P"+1)