若|a-3|与|b-2|互为相反数,则3a-2b的值为? 如果|a-3|与根号b-3互为相反数,那么根号a+2b的值?
\u82e5a\u51cf3\u7684\u7edd\u5bf9\u503c\u4e0eb\u51cf2\u7684\u7edd\u5bf9\u503c\u4e92\u4e3a\u76f8\u53cd\u6570\uff0c\u52193a\u51cf2b\u7684\u503c\u662f\u591a\u5c11\u6839\u636e\u9898\u610f\u5f97\uff1a
|a-3|+|b-2|=0\uff0c
a-3=0\uff0cb-2=0\uff0c
a=3\uff0cb=2\uff0c
\u22343a-2b
=3\u00d73-2\u00d72
=5\u3002
|a-3|\u4e0e\u6839\u53f7b-3\u4e92\u4e3a\u76f8\u53cd\u6570
\u6240\u4ee5|a-3|+\u6839\u53f7b-3=0
\u7edd\u5bf9\u503c\u548c\u6839\u53f7\u90fd\u5927\u4e8e\u7b49\u4e8e0\uff0c\u76f8\u52a0\u7b49\u4e8e0\uff0c\u82e5\u6709\u4e00\u4e2a\u5927\u4e8e0\uff0c\u5219\u53e6\u4e00\u4e2a\u5c0f\u4e8e0\uff0c\u4e0d\u6210\u7acb\u3002
\u6240\u4ee5\u4e24\u4e2a\u5f0f\u5b50\u90fd\u7b49\u4e8e0
\u6240\u4ee5a-3=0,b-3=0
a=3,b=3
a+2b=3+6=9
\u6240\u4ee5\u6839\u53f7a+2b=3
|
a
-
3
|
与
|
b
-
2
|互为相反数
所以
|
a
-
3
|
+
|
b
-
2
|
=
0
因为绝对值大于等于0
两个大于等于0的数相加等于0
说明每个数都等于0
所以
a
-
3
=
0
,
b
-
2
=
0
所以
a
=
3
,b
=
2
所以
3a
-
2b
=
3
×
3
-
2
×
2
=
5
绛旓細瑙o細|b-2|涓(a+1)²浜掍负鐩鍙嶆暟锛屽垯|b-2|+(a+1)²=0锛岃В寰楋細a=-1锛宐=2 鏁卆^b=(-1)²=1
绛旓細瑙o細 |b+2|+锛a-3锛=0銆 鍥犱负|b+2|鈮0锛岋紙a-3锛夆墺0 鎵浠+2=0锛宎-3=0 鎵浠=3锛宐=-2 b鐨刟娆℃柟=-2鐨3娆℃柟=1/8
绛旓細鑻ワ綔a锕2锝滀笌锝渂锕3锝滀簰涓虹浉鍙嶆暟锛岄偅涔坅=2锛宐=3銆傚垯2b锕鐨勫兼槸.4銆傚洜涓猴綔a锕2锝滀笌锝渂锕3锝滃潎涓洪潪璐熸暟锛屾墍浠ュ彧鏈夛紳0銆
绛旓細鍥犱负|a-3|涓巪2b-4|浜掍负鐩鍙嶆暟锛屽張缁濆鍊奸兘涓嶅彲鑳藉皬浜0锛屾墍浠ヨ涓轰袱涓浉鍙嶆暟锛屽垯涓ゆ暟鍙兘涓0.鍗 a-3=0涓2b-4=0銆傚緱a=3锛宐=2
绛旓細褰|a-2|涓巪b+3|浜掍负鐩稿弽鏁版椂 蹇呮湁a-2=0 b+3=0 鍥犱负鍔犵粷瀵瑰煎彿鐨勫煎ぇ浜庢垨绛変簬闆 鑰屼袱鏁涓虹浉鍙嶆暟 鍒欎袱鏁伴兘蹇呴』涓洪浂 鎵浠=2 b=-3 鎵浠+b= -1
绛旓細琛ュ厖绗1鏉★細杩欏鐩稿弽鏁颁竴瀹氫负缁濆鍊笺2銆佸湪鏁拌酱涓婏紝浜掍负鐩鍙嶆暟锛0闄ゅ锛夌殑涓や釜鐐逛綅浜庡師鐐圭殑涓ゆ梺锛屽苟涓斿叧浜庡師鐐瑰绉般3銆佹鏃讹紝b鐨勭浉鍙嶆暟涓猴梗b=锕(锕)=a锛岄偅涔堟垜浠氨璇粹滅浉鍙嶆暟鍏锋湁浜掔О鎬р濄傛敞鎰忊滀簰涓虹浉鍙嶆暟鈥濆拰鈥滅浉鍙嶆暟鈥濆湪姒傚康涓婄殑鍖哄埆銆
绛旓細缁濆鍊奸兘澶т簬绛変簬0 鎵浠|3-a|涓巪b-1|閮芥槸0 a=3,b=1 2/a-b=-1/3
绛旓細a-2鐨勭粷瀵瑰涓巄-3鐨勭粷瀵瑰浜掍负鐩鍙嶆暟 鎵浠-2鐨勭粷瀵瑰+b-3鐨勭粷瀵瑰=0 鍥犱负a-2鐨勭粷瀵瑰尖墺0锛宐-3鐨勭粷瀵瑰尖墺0 鎵浠-2=0锛宐-3=0 鎵浠=2锛宐=3
绛旓細|a+2|涓巪b-3| 浜掍负鐩鍙嶆暟 |a+2|涓巪b-3|閮芥槸闈炶礋鏁 绗﹀悎涓婇潰涓や釜鏉′欢鐨勶紝鍙兘鏄瘄a+2|涓巪b-3|閮戒负0 鎵浠+2=0涓攂-3=0 a=-2锛宐=3 a+b=-2+3=1
绛旓細鈭|a-2|涓巪b+3|浜掍负鐩鍙嶆暟锛屸埓|a-2|+|b+3|=0锛屸埓a-2=0锛宐+3=0锛岃В寰梐=2锛宐=-3锛屾墍浠ワ紝a+b=2+锛-3锛=-1锛庢晠绛旀涓猴細-1锛