初二数学解方程要过程要检验!谢谢 初二数学题 解方程 (x的平方-1)的平方-2(x的平方-1...
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\u89e3\uff1a\u4ee4t=X2-1
\u5219t2-2t-3=0
t=3\u6216-1
\u5219X2-1=3\u6216-1
x=2\uff0c-2 \u62160
绛旓細瑙o細600/x锛2100/x锛9 2700/x锛9 x锛300 缁妫楠锛歺锛300鏄師鏂圭▼鐨勮В銆60/x锛120/x锛9 180/x锛9 x锛20 缁忔楠岋細x锛20鏄師鏂圭▼鐨勮В銆
绛旓細楠岃瘉锛歺=4鍘鏂圭▼鏈夋晥锛屾晠瑙d负锛歺=4
绛旓細浜烘暀鐗堝垵浜鏂圭▼鏄垎寮忔柟绋嬨傝В鍒嗗紡鏂圭▼鐨勬楠わ細涓锛屽幓鍒嗘瘝銆傛柟绋嬬殑涓よ竟鍚屾椂涔樹互鍚勫垎姣嶇殑鏈绠鍏垎姣嶏紝鎶婂垎寮忔柟绋嬭浆鍖栦负鏁村紡鏂圭▼锛涗簩锛岃В杩欎釜鏁村紡鏂圭▼锛涗笁锛妫楠銆傛妸鏂规暣寮忔柟绋嬬殑瑙e甫鍏ュ埌鏈绠鍏垎姣嶏紝浣挎渶绠鍏垎姣嶄负闆剁殑鏍规槸鍒嗗紡鏂圭▼鐨勫鏍广備娇鏈绠鍏垎姣嶄笉涓洪浂鐨勬牴鏄師鍒嗗紡鏂圭▼鐨勬牴銆
绛旓細1銆鏂圭▼涓よ竟閮戒箻浠(X-2)锛1+(1-X)=X-2锛2X=4 X=2 缁妫楠X=2鏄鏍癸紝鈭村師鏂圭▼鏃犺В銆2銆佹柟绋嬩袱杈归兘涔樹互(2X-5)锛歑-5-(2X-5)=0 -X=0 X=0锛岀粡妫楠孹=0鏄師鏂圭▼鐨勬牴銆
绛旓細鍥炵瓟锛氳В:鍘诲垎姣嶅緱 (x-2)²-12=x²-4 鈭磝²-4x+4-12=x²-4 -4x=4 鈭磝=-1 妫楠:x²-4鈮0 鈭村師鏂圭▼鐨勬牴鏄 x=-1
绛旓細(1)瑙o細涓よ竟涔(x+1)(x-1)(x+1)²-4=(x+1)(x-1)x²+2x+1-4=x²-1 2x=2 x=1 缁妫楠锛寈=1鏃跺叕鍒嗘瘝(x+1)(x-1)=0 鏄鏍癸紝鑸嶅幓 锛2锛夎В锛氬師寮忎袱杈逛箻浠ワ紙x-3锛夊寲涓猴細1+2锛坸-3锛=x-4 鍗筹細2x-5=x-4 x=1 缁忔楠岋紝x=1鏃跺叕鍒嗘瘝锛坸-3锛夆墵0 鎵...
绛旓細瑙o細鏂圭▼涓よ竟鍚屾椂涔樹互2(2-x)锛屽緱锛-1+(2-x)=3脳2 1-x=6 瑙e緱 x=-5 浠e叆楠岃瘉鐭ワ紝x=-5灏辨槸鍘熸柟绋嬬殑鏍 涓嶆眰閫熷害锛屼絾姹傝川閲忥紝鏀惧績閲囩撼锛屾杩庤拷闂
绛旓細x+y=16鈶 0.4x+y=9.4鈶 鐢(1)寰 y=16-x (3)(3)浠e叆(2)寰 0.4x+16-x=9.4 -0.6x=-6.6 鈭磝=11 鎶妜=11浠e叆(3)寰 y=16-11=5 鈭磝=11 y=5
绛旓細瑙 涓よ竟鍚屾椂涔樹互x(x-2)寰楋細(x-2)²-2x²=-x(x-2)x²-4x+4-2x²=-x²+2x -x²+x²-4x-2x=-4 -6x=-4 x=2/3 缁妫楠x=2/3鏄鏂圭▼鐨勮В 鏂圭▼涓よ竟鍚屾椂涔樹互1-x²寰楋細2(1-x)-3(x+1)=3 2-2x-3x-3=3 -5x=3+1 -5x=4 x=-...
绛旓細1.瑙o細鍥犱负姝鏂圭▼缁勭殑瑙锛寉鐨勫拰涓6锛屾墍浠=6-y锛屽皢x=6-y浠e叆2x+3y=k 寰 2(6-y)+3y=k 寰 12+y=k (1)灏唜=6-y浠e叆 3x+2y=k+2 寰3(6-y)+2y=k+2 寰 16-y=k (2)(1) 涓(2)缁勬垚鏂圭▼缁勫緱 12+y=k 16-y=k 瑙e緱k=14 y=2 2.瑙o細鏂圭▼ x...