tính nhanh
a,101^2
b,97x103
c,77^2+23^2+77x46
d,105^2-5^2
Tính nhanh:
a.1012 b.97×103 c.772+232+77×46
d.1052-5
1012
= (100 + 1)²
= 100² + 2.100.1 + 1²
= 10000 + 200 + 1
= 10201
a. 1012 = 10201
b. 97 x 103 = 9991
c. 772 + 232 + 77 x 46
= 5929 + 529 + 77 x 46
= 5929 + 529 + 3542
= 6458 + 3542
= 10000
d. 1052 - 5
= 11025 - 5
= 11020
a)1012 =10201
b)97x103=9991
c)772 +232 +77x46=3136564
d)1052 -5=11020
Tính nhanh:
a) 101^2
B)97*103
C) 772+232+77*46
D) 1052-52
a) 1012
= (100 + 1)2
= 1002 + 2.100 + 1
= 10000 + 200 + 1
= 10201
b) 97.103
= (100 - 3)(100 + 3)
= 1002 - 32
= 10000 - 9
= 9991
c) 772 + 232 + 77.46
= 772 + 2.77.23 + 232
= (77 + 23)2
= 1002
= 10000
d) 1052 - 52
= (105 - 5)(105 + 5)
= 100.110
= 11000
Tính nhanh 772+232+77x46
772 + 232 + 77.46 = 772 + 232 + 2.77.23
= (77 + 23)2 = 1002 = 10000
Tính nhanh:
a. 101²
b. 97×103
c. 77²+23²+77*46
d.105²-5²
a.\(^{101^2}\)= 10201
b.97 x 103 = 9991
c.\(^{77^2}+^{23^2}+77\times46\)=10000
d.\(^{105^5}-^{5^2}\)= 12762815600
a) 1012 = (100 - 1)2 = 1002 - 200 + 1 = 10000 - 200 + 1 = 9801
b) 97 x 103 = (100 - 3)(100 + 3) = 1002 - 32 = 10000 - 9 = 9991
c) 772 + 232 + 77*46 = (77 + 23)2 = 1002 = 10000
d) 1052 - 52 = (105 + 5)(105 - 5) = 110 * 100 = 11000
Tìm x biết:
a. (x-2)²-(x-3)(x+3)=6
b. 4(x-3)²-(2x-1)(2x+1)=10
Bài `3` Tính nhanh
`a,101^2-99^2`
`b,98.102`
`c,77^2+23^2+77.46`
\(a.101^2-99^2=\left(101+99\right)\left(101-99\right)=200.2=400\)
\(b.98.102=98.\left(100+2\right)=9800+196=9996\)
\(c,77^2+23^2+77.46=77^2+23^2+2.77.23=\left(77+23\right)^2=100^2=10000\)
tính nhanh
a, 101^2-99^2
b,98.102
c,77^2+23^2+77.46
Tính nhanh
A=2/1*5+2/5*9+2/9*13+...+2/97*101+2/101*105
B=4/2*5+4/5*2+4/8*11+...+4/44*47+4/47*50
C=3/1*3*5+3/3*5*7+3/5*7*9+...+3/19*21*23+3/21*23*25
A = 2/1*5 + 2/5*9 + ... + 2/101*105
= 1/2(4/1*5 + 4/5*9 + ... + 4/101*105)
= 1/2(1 - 1/5 + 1/5 - 1/9 + ... + 1/101 - 1/105)
= 1/2(1 - 1/105)
= 1/2 * 104/105 = 52/105
Sửa câu b. Phân số thứ 2 phải là 4/5*8
B = 4/2*5 + 4/5*8 + ... + 4/47*50
= 4/3(3/2*5 + 3/5*8 + ... + 3/47*50)
= 4/3(1/2 - 1/5 + 1/5 - 1/8 + ... + 1/47 - 1/50)
= 4/3(1/2 - 1/50)
= 4/3 * 24/50 = 16/25
Tính nhanh
\(101^2\)
97.103
\(77^2+23^2+77.46\)
\(105^2-5^2\)
1012 = (100 + 1)2 = 100² + 2.100.1 + 1² = 10000 + 200 + 1 = 10201
97 . 103 = (100 - 3)(100 + 3) = 1002 - 32 = 10000 - 9 = 9991
772 + 232 + 77.46 = 772 + 2. 23. 77 + 232 = (77 + 23)2 = 1002 = 10000
1052 - 52 = (105 - 5)(105 + 5) = 100 . 110 = 11000
tick nha
Tính nhanh
\(101^2\)
97.103
\(77^2+23^2+77.46\)
\(105^2-5^2\)
a) \(101^2\)
\(=\left(100+1\right)^2\)
\(=100^2+2.100.1+1^2\)
\(=10000+200+1\)
\(=10200+1\)
\(=10201\)
b) \(97.103\)
\(=\left(100-3\right).\left(100+3\right)\)
\(=100^2-3^2\)
\(=10000-9\)
\(=9991\)
c) \(77^2+23^2+77.46\)
\(=77^2+77.46+23^2\)
\(=77^2+2.77.23+23^2\)
\(=\left(77+23\right)^2\)
\(=100^2\)
\(=10000\)
d) \(105^2-5^2\)
\(=\left(105-5\right)\left(105+5\right)\)
\(=100.110\)
\(=11000\)
lâu lắm r moi lên h24, tớ giúp bn nhé:
*1012 = (100+1)2 = 104 + 2.100.1 +12 = 10201
*97.103= (100-3)(100+3) = 102 - 32 = 9991
* = 772 + 2.77.23 + 232 = (77+23)2 = 104