因式分解:(a+b)^2-8(a^2-b^2)+16(a-b)^2

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因式分解:(a+b)^2-8(a^2-b^2)+16(a-b)^2
因式分解:(a+b)^2-8(a^2-b^2)+16(a-b)^2

因式分解:(a+b)^2-8(a^2-b^2)+16(a-b)^2
( a + b )" - 8( a" - b" ) + 16( a - b )"
= ( a + b )" - 8( a + b )( a - b ) + 16( a - b )"
= ( a + b )" - 2( a + b )( 4a - 4b ) + ( 4a - 4b )"
= [ ( a + b ) - ( 4a - 4b ) ]"
= ( a + b - 4a + 4b )"
= ( -3a + 5b )"
= ( 3a - 5b )"

运用换元法:(a+b)²-8(a²-b²)+16(a-b)²
=(a+b)²-2×4×(a+b)(a-b)+[4(a-b)]^2
=[(a+b)-4(a-b)]²
=(5b-3a)²
望楼主采纳!

(a+b)^2-8(a^2-b^2)+16(a-b)^2
=(a+b)^2-2×4×(a^2-b^2)+[4(a-b)]^2
=[(a+b)-4(a-b)]^2
=(5b-3a)^2