Tính nhanh
a) 23 - 21 + 19 - 17 + 15 - 13 + 11 - 9 + 7 - 5 + 3 - 1;
b) 24 - 22 + 20 - 18 + 16 - 14 + 12 - 10 + 8 - 6 + 4 - 2
 

a)\(\frac{45^{10}.5^{10}}{75^{10}}\)

b)\(\frac{8^{10}+4^{10}}{8^4+4^{11}}\)

c)\(\frac{4^{20}-2^{20}+6^{20}}{6^{20}-3^{20}+9^{20}}\)

d) \(\frac{14^{16}.21^{32}.45^{48}}{10^{16}.15^{32}.7^{96}}\)

1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37=

Tính nhanh:

A=1+1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20=

B=20+21+22+23+24+25=

C=26+27+28+29+30+31+32+33=

D=1+(tổng các số đến 100)=

1+2+3+4+5+6+7+8+9+10=

11+12+13+14+15+16+17+18+19+20=

1+2+3+4+5+6+7+8+9+10+11+12+13+14 +15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30-50-53=
bạn5 bạn nào làm nhanh mình sẽ tích cho bạn đó 

tính 1*2*3*4*5*6*7*8*9*10*11*12*13*14*15*16*17*18*19*0*20*21*22*23*24*25*26*27*28*29*30*31*32

ai nhanh mình tích cho

1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+149+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39*100

1+2+3+4+5+6+7+8+9+10=

11+12+13+14+15+16+17+18+19+20=

1+2+3+4+5+6+7+8+9+10+11+12+13+14 +15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30-50-53=bạn5 bạn nào làm nhanh mình sẽ tích cho bạn đó 

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