△表示一种运算其意义是a△b=2a-b,计算(6△4)△7
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得3826乘5得304乘4得162乘5得107乘4得2830加16乘5得23010加28乘4得152230加152得382
由题知:a△b=ab分之a-2b,则:先算4△3),把a=4,b=3,代入a△b=ab分之a-2b就是了,算出来,后面也是一样.这题目好简单的,别想得太难咯.4△3=12∕(4-6)=-6,3△(4△
a△b=(a+b)/210△0.8=(10+0.8)/2=5.4
1△3=2*1-3=-1x△-1=2*x+1=+/-2x=1/2or-3/2
(3#4)#(-5)=-3*4-(3+4)#(-5)=(-19)#(-5)=-19*5-(-19-5)=-71
(9△7)△(5△3)=(2*9-7)△(2*5-3)=11△7=(2*11-7)=15
(6△7)△(5△3)=(6x2-7)△(5x2-3)=5△7=5x2-7=3
2△x=5(2)+2x=10+2x=2810+2x=282x=28-102x=18x=9
∵x△(1△3)=2,x△(1×2-3)=2,x△(-1)=2,2x-(-1)=2,2x+1=2,∴x=12.
x@(3@4)=2x@(2*3-4)=2x@2=22x-2=22x=2+22x=4x=2
1*3=2-3=-1|x*(-1)|=|2x-(-1)|=|2x+1|=22x+1=2或2x+1=-2解得x=-1.5或1/2
“*”表示一种新运算,它的意义是a*b=-a*b-(a+b).求:(1)3*5=3*5-(3+5)=15-8=7(2)(-3)*(-5)=[(-3)*(-5)-(-3-5)=15+8=23
(1)(-2)(*)(-3)=-(-2)*(-3)-(-2-3)=-6+5=-1(2)(3(*)4)(*)(-5)=[-3*4-(3+4)](*)(-5)=(-12-7)(*)(-5)=(-19)(*
(-3)*5=-(-3)×5-(-3+5)=15-2=-13(-4)*(-5)=-(-4)×(-5)-[(-4)+(-5)]=-20-(-9)=-11
题中等号后=-axb中x是正常乘法吗?"x"可以是:×(-1)×a"x"b=a×(-1)×b=-a×
3*5=-3x5-(3+5)=-15-8=-23(-3)*(-5)=-(-3)x(-5)-[(-3)+(-5)]=-15-(-8)=-7
因为a*b=-a乘b-(a+b)3*5=-3X5-(3+5)=-23-3*(-5)=-(-3)X(-5)-(-3+-5)=-7
a△b=2a-b-1/2△(-1△3)=-1/2△[2×(-1)-3]=-1/2△(-5)=2×(-1/2)-(-5)=-1+5=4