小学六年级奥数专项常考题汇编-计算问题—定义新运算(含答案).docx
六年级奥数专项精品讲义常考题汇编-计算问题一定义新运算一.选择题1. “”表示一种运算符号,其意义是:ab = 2a-b,如果X4(243) = 3,贝Ux = ()A. 2B. 3C. 4D. 52.我们可以把QXaXQXQ (共个相乘)记为q",例如3x3xx3 (共6个3相乘)=729, 现规定如下:如果正整数Q , n,b满足/=,贝U记作 = QW)根据上述规定判断下列哪个是 错误的?()A. 23×33 =63B. 2(×)4 = 3(×)9C. 303 + 3027 = 3081D. (309)x(303) = 30273 .如果定义=那么 7Z9 = ()A. 56B. 45C. 77D. 144 .定义+ 为A的3倍减去6的2倍,即A+6 = 3A-26,已知X+ (4+1) = 7,贝IJX =( )A. 7B. 8C. 9D. 105.规定一种运算:。6= S + )xb,则(3X2)X4 = ()A. 56B. 40C. 9D. 246.定义运算“ *“: ab = a×b + b,如 2*3 = 2x3 + 3 = 9,贝 J(4*5)*2 = ()A. 48B. 50C. 51D. 527.规定:ab = 3a-2b.已知XZ(441) = 7,那么 XZ5 = ()A. 7B. 17C. 9D. 19 E.368 .如果规定人派5 = 3,如1X2 = =,那么10X(10 X 10)的值等于()A + B1 + 2A. -B. C. -D. 3333二.填空题9 .若 243 = 2 + 3 + 4 = 9, 54 = 5 + 6 + 7 + 8 = 26,按止匕规律必3 =.10 .规定加 N = 5f 4N,若不(5 X 2) = 14,则 X =.11 .如果规定*/? = +,例如4*3 = 3?+4 = 13,那么 7*0.8=.12 .设A、6都表示数,规定A表示A的4倍减去5的3倍,即:AB = 4×A-3×B .计算 56的结果为.13 .规定:AB = 5A-4B .如果 X (5 2) = 14 ,那么 X=.14 . = ( + 5)×(-3),计算 3Z7=.15 .规定种运算:q#Z? = " + 2q-1,贝|6#5 =16 .对于数 a、b > c > d ,规定,<、b > c > d >= 2ab -c + d .(1) <1、3、5、2>=;(2) <1、3、5、x>=7 , X -.三.计算题17 . *代表一种运算法则,如果A*5 = (A + 8)÷2那么10*(16*24)得多少?18 .定义:a b = a×b-a + b)试求:6 : (4 3)19 .已知242 = 5, 34 = 18, 43 = 15,你能计算743, 6Zk4各是多少吗?四.解答题20 .规定:q* = 4xq-3xb,求5*4=.21 .规定新运算:a®b = a2 -b , a®b = a + ba-b),若根是大于10的最小的合数,是最小的质数,求机(机几)的值.22 .如果,3 = !,2 =!义工;那么请你探究:!3=,派4 ,4=.22 3 477 832323 .如果规定*b = 5x-Lxb (其中。,人是自然数),那么2(1) 10*6 =(2) 6*10 =24 .求下列方程的解.2% 1.65 + 2.35 = 7规定A*6 = 3A + 46,已知7*% = 45,求x.25 .特殊计算(1)如果="-,求 oaozo 的值. a + b(2)若“ !”是一种数学运算符号,并且 1! =1, 2! =2×1, 3! =3x2xl = 6, 4! =4x3x2x1 = 24,且公式G = 伽1)52)(一加+1),求仁的值."m26 .列式计算(1)如果 = "-,求 10410 的值. a + b(2)若“ !”是一种数学运算符号,并且 1! =1, 2! =2×1 = 2, 3! =3x2xl = 6,4! =4x3x2x1 = 24,且公式C;= 伽 1)(-2)(加+ 1),求点的值.27 .规定、两数中较大的数减去较小的数得到的结果记为,例如:142 = 1; (12)3 = 2;(12)34 = 2;则(14 2)4 3) 4) 99) 4lOO =六年级奥数专项精品讲义常考题汇编-计算问题一定义新运算参考答案一.选择题1 .解:H23 = 2×2-3 = l,所以 X4(243) = 3,xl = 3,2%-1 = 3,2% 1 + 1 = 3 + 1,2x = 4,x = 2 ;答案:A.2 .解:A、 23×33 =2×2×2×3×3×3 = 6×6×6 = 63,正确;B、2?=4, 32=9, 2 04 = 2, 3(S)9 = 2, 204 = 309,正确;C> 31=3, 33=27, 34=81, 303 = 1, 3027 = 3 , 3081 = 4, 1 + 3 = 4, 303 + 3027 = 3081,正确;D> 31=3, 32=9, 33=27, 3(×)9 = 2, 303 = 1, 3027 = 3 , 1×23, (39)x(33) = 327 ,不正确.答案:D.3 .解:79= 2x7x9-92= 126 81=45 ;答案:B.4 .解:因为,41 = 3×4-2×l = 12-2 = 10,所以,x(41) = 7 ,即,xl = 7,3% 2x10 = 7,3x = 27,% = 27 ÷ 3 ,答案:C.5 .解:3X2 = (3 + 2)x2 = 1010X4 = (10 + 4)x4 = 56所以(3 X 2) X 4 = 56.答案:A .6 .解:(4*5)*2,= (4x5 + 5)*2,= 25*2,=25 X 2 + 2 ,= 52;答案:D.7 .解:41 = 3×4-2×1,= 10,x(4l) = 7 ,xl = 7,3-2×10 = 7,3x20 = 7,3 元= 20 + 7,3x = 27,% = 27÷3,x = 9 ;5 = 95,=3x92x5,= 27 10,答案:B.IOxlO10 + 10二 10X5,_10-T,答案:B.二.填空题9 .解:43 = 4 + 5 + 6 = 15, 答案:15.10 .解:X X (5 X 2) = 14x(5×5-4×2) = 14117 = 145x-4×17 = 145x = 82X = I6.4答案:16.4.11 .解:7*0.8= 0.82+7= 7.64答案:7.64.12 .解:56=4×5-3×6= 20 18=2答案:2.13 .解:x(52) = 14x(5×5-4×2) = 14x17 = 145% 4x17 = 145x-68 = 145 %= 14 + 685% = 82% = 16.4答案:16.4.= (3 + 5)×(7-3)= 8x4=32答案:32.15 .解:6#5=6×5+2×6-1= 30 + 12-1=41答案:41.16 .解:(1) <1、3、5、 2> =2×l×3-5+2=3(2) <1 > 3、5、x> =2×l×3-5+x即2×l×3-5 + x = 7l + l = 7x = 6答:x = 6.答案:3; 6.三.计算题17.解:10*(16*24)= IoM(16 + 24) ÷ 2= 10*40÷2= 10*20= (10 + 20)÷2= 30÷2二15答:10*(16*24)得 15.18 .解:6>(4O3)=6 _ 5= 6×5-(6 + 5) = 30-11=1919 .解:73=7+8+9=2464=6+7+8+9= 13 + 8 + 9=30答:743的结果是24, 644的结果是30.四.解答题20 .解:5*4=5×4-3×4= 20 12=8 .答案:8.21 .解:根据题意可得,机= 12, = 2;机(根几)=12(12名)2)= 12© (12+ 2)(12-2)=12 14 X10二12 140= 122-140= 144-140=4 60;,4派42311111111=× × ×× × × 23453456J1-1203601-180;答案:;- -6018023.解: 10*6= 5×10-×62= 50 3 =47 6*10= 5×6-×10 2= 30 5 =25答:10*6 = 47, 6*10 = 2524.解:(1) 2% 1.65 + 2.35 = 72% 0.7 = 72x 0.7 + 0.7 = 7 + 0.72%÷2 = 7.7÷2尤=3.85 ;(2)依据题意可得:7*% = 453×7 + 4x = 4521 + 4x-21 = 45-214%÷4 = 24÷425.解:(1)因为:a b =aba + b所以:10101010 + 10= 510_ 5×10-5 + 10_10T(2)因为:1! =1, 2! =2×1, 3! =3x2xl = 6, 4! =4x3x2x1 = 24且公式cm =以DS2)(加+D "m所以:5 _ 8x(8 1)x(8 2)><(8 3)><(8 5 + 1)8 5×4×3×2×18×7×6×5×4120=5626.解:(1) 1010 10xl0 510 + 10-5=8x(8-1)x(8 2)义义(8 5 + 1)8 58×7×6×5×4一 5= 1344.27.解:因为 1Z2 = 1,13 = 2,24 = 2,25 = 3,36 = 3,37 = 4,48 = 4,49 = 5,由此,依此类推,得出当后面的数是偶数时,它的值是这个偶数除以2, (l2)3)4).99) l = l÷2 = 50.