3*99=
1+1+1+1+2+2+2+2+3+3+3+3+...+99+99+99+99+100+100+100+100=?
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==========================ko bt
( ;-; )
99^3 + 1 + 3.(99^2 + 99)
993+1+3.(992+99)=993+3.992+3.99+1
=(99+1)3=1003=1000000
Tính 99^3+1+3 nhân (99^2+99)
\(99^{3+1+3}.\left(99^2+99\right)=99^7.\left(99^2+99\right)=99^7.99^2+99^7.99=99^{99}+99^{98}\)
tính nhanh (2/3+3/4+5/6+...+99/100).(1/2+2/3+3/4+...+98/99)-(1/2+1/3+...+99/100).(2/3+2/4+...+98/99)
Cho mik hỏi cách làm bài này
Tính nhanh 1 1/2x1 1/3 × 11/4×...x 1 1/99×1 1/100
99 x 95 + 99 x 3 + 99 + 99
99 x 95 + 99 x 3 + 99 + 99
= 99 x ( 95 +3 ) + ( 99 + 99 )
= 99 x 98 + 198
= 9702 + 198
= 9900
99 x 95 + 99 x 3 + 99 + 99= 9405 + 297 + 198
=9900
a) 99 x 95 + 99 x 3 + 99 + 99
= 99 x 95 + 99 x 3 + 99 x 1 + 99 x 1
= 99 x ( 95 + 3 + 1 + 1 )
= 99 x 100
= 9900
(1+97)*(1+97/2)*(1+97/3)*(1+97/4)... ... ...(1+97/99)
(1+99)*(1+99/2)*(1+99/3)*(1+99/4)... ... ...(1+99/97)
\(99^{99}\)-\(\left\{1,\left(3\right)-\left[5\times2^3-\left(-7^2\right)+\dfrac{1}{3}+99^9\times\left(27^4-81^3-99^{90}\right)\right]\right\}\)
tìm chữ số tận cùng của 1^99+2^99+3^99+...+99^99
chữ số tận cùng: = 0
993 + 1 + 3.(992 + 99)