c^2 - d^2 + 3c - 3d
over
c^2 - d^2
MATHS
2007-08-30 5:21 am
回答 (3)
2007-08-30 5:28 am
✔ 最佳答案
( c^2 - d^2 + 3c - 3d ) / ( c^2 - d^2 ) = {(c+d)(c-d)+3(c-d)}/(c+d)(c-d) { By a^2 - b^2 = ( a + b )( a - b ) }
= ( c - d )( c + d + 3 ) / ( c + d )( c - d ) { Factorization }
= ( c + d + 3 ) / ( c + d )
參考: My Maths Knowledge
2007-08-30 5:49 am
(c^2 - d^2) +(3c - 3d) / (c^2 - d^2 )
=(c+d)(c-d)+3(c-d) / (c+d)(c-d)
=(c-d)[ (c+d)+3] / (c+d)(c-d)
=(c+d)+3 / (c+d)
=(c+d) / (c+d) + 3 / (c+d)
=1+ 3/(c+d)
=(c+d)(c-d)+3(c-d) / (c+d)(c-d)
=(c-d)[ (c+d)+3] / (c+d)(c-d)
=(c+d)+3 / (c+d)
=(c+d) / (c+d) + 3 / (c+d)
=1+ 3/(c+d)
2007-08-30 5:31 am
(c^2 - d^2) +(3c - 3d) / (c^2 - d^2 )
=(c+d)(c-d)+3(c-d) / (c+d)(c-d)
=(c-d)[ (c+d)+3] / (c+d)(c-d)
=(c+d)+3 / (c+d)
=(c+d) / (c+d) + 3 / (c+d)
=1+ 3/(c+d)
=(c+d)(c-d)+3(c-d) / (c+d)(c-d)
=(c-d)[ (c+d)+3] / (c+d)(c-d)
=(c+d)+3 / (c+d)
=(c+d) / (c+d) + 3 / (c+d)
=1+ 3/(c+d)
收錄日期: 2021-04-20 18:36:31
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