人教版八年级下册数学知识点归纳

1.aa02.3.4.1a2=aa02aa25.123ab=a2ba0b0bbaab0a041.abca2b2=c21ABC90C22cab22bca22acb22.a,b,ca2b2=c23.aa0aa00a=04.222abcabcabc3,4,56,8,105,12,137,24,255.1C=90A+B=90230A=30BC=21ABC=903ACB=90CD=21AB=BD=ADDAB6ABCD=ACBC7123abc222cba811223451239121234510..::113602360.21n(n-2)1802360.3ABCD.543214.ABCD54321.5.ABCD.3;2;16.321ABCD.7ABCD.321ABCD1234ABCDABDOCCDBAOABDOCADBCADBCADBCOADBCO8321ABCD.9ABCD.321CDAB1ABCDO2310321ABCD.(3)ABCDAD=ABABCD11ABCD.32112321ABCD(3)ABCDADBCAC=BDABCD14.DEABCDEBCDE=21BC15.EFDABCEDCBACDBAOABCDOABCDOCDAB1S=21ab=ch.ab,chc2S=ah.aha3S=21a+bh=Lh.abh,L1n2)3n(n.2.3,,..,,xyxyxyx1203451231231y=kx(kk0).k1kk021(3)2:1)y=kx(kk0))y=kx001k(2):k0,y=kxxyk0,y=kx,xy1y=kx+b(k,bk0).b=0,y=kx+by=kx,.1k2x134b21y=kx+b0b-kb0y=kx+b,y=kx|b|.b0b02b0y=kxbb0y=kxb.30b-kb04y=kxb..b0b0b=0k0yxk0yx12xy34.y=k1x+b1y=k2x+b2k1=k2b1b21.xy=ax+b02.ax+b=0(a,ba0)y=ax+bx3.ax+b0(aba0)xy=ax+b04.ax+b0(aba0)y=ax+bx5.x.1.1nnxxxxn21.2x1w1x2w2,xnwn:2.3.4.cbacbayxyx222111cbacbayxyx22211112,,35.6.nnxxx212221)()(xxxx,2)(xxn])()()[(1222212xxxxxxnSn222211xxxxxxnSn