\(=\left(6^2-1\right)+\left(7^2-2^2\right)+\left(8^2-3^2\right)+\left(9^2-4^2\right)+\left(10^2-5^2\right)\)
\(=5\left(1+2+...+9+10\right)=5\cdot55=275\)
\(=\left(6^2-1\right)+\left(7^2-2^2\right)+\left(8^2-3^2\right)+\left(9^2-4^2\right)+\left(10^2-5^2\right)\)
\(=5\left(1+2+...+9+10\right)=5\cdot55=275\)
Hãy điền các dấu +,-,x,:,( ), ngoặc vuông, ngoặc nhọn,... để kết quả là -1
1...2...3...4=-1
1...2...3...4...5=-1
1...2...3...4...5...6=-1
1...2...3...4...5...6...7=-1
1...2...3...4...5...6...7...8=-1
1...2...3...4...5...6...7...8...9=-1
1...2...3...4...5...6...7...8...9...10=-1
Tính:
1) (-6 - 2 ) . (-6 + 2 )
2) ( 7 . 3 - 3 ) : (-6)
3) (-5 + 9 ) . (-4 )
4) 72 : (-6 . 2 + 4 )
5) -3 . 7 - 4 . (-5) + 1
6) 18 - 10 : (+2 )- 7
7) 15 : (-5) . (-3) -8
8) (6.8 - 10 : 5) + 3 . (-7)
(Mk cần gấp )
tinh :
(6^2+7^2+8^2+9^2+10^2)-(1^2+2^2+3^2+4^2+5^2)
2/5-2/9+2/11/7/5-7/9+7/11:1/3-1/4+1/5/7/6-7/8+7/10:tính nhanh
Giải giúp mình nha:
1. Tính hợp lí:
1, 3. (-4 )2 + 2. (-5 ) -20 2, 31 - [26 - (209 + 35) ]
3, 231 + 26 - (209 + 26) 4, 19. 25 + 9. 95 + 19. 30
5, (-50 + 19 + 143) - (-79 + 25 +48) 6, 160 : {|-17 | + [ 32. 5 - (14 + 211 : 28)]}
7, |-6| + (-7) + | -4 | + ( -3 ) 8, 23 . 5 - 32 . 4 + 4. 6
9, 56 : 53 - 50 . 51 . 52 10, 16. (38 - 2) - 38.(16 - 1)
Xin cảm ơn !!!
viết kết quả sau dưới dạng một lũy thừa
a) 38 :36 ; 197 :193 ; 210:83 ; 127 :67 ; 275 :813
b, 106 :10 ; 58 :252 ; 49 :642 ; 225: 324 ; 183 : 93
\(\dfrac{2^{12}.3^5-4^6.9^2}{\left(2^3.3\right)^6+8^4.3^5}-\dfrac{5^{10}.7^3-25^5.49^2}{\left(127.7\right)^3+5^9+14^3}\)
Tìm x :
1/ |x-5|-7(x+4)=5-7x
2/3|x+4|-2(x+1)=7-2x
3/2|x-6|+7x-2=|x-6|+7x
4/|x+8|+(x-2)=5x-10:2
5/|x+2|-6(x-4)=20-6x
20:22-59:58 29-[16+3.(51-49)]
(519:517-4):7 47.(45.24-52.12):14
-84:4+39:37+50 102-60:(56:54-3.5)
295-(31-22.5)2 2345-1000:{19-2(21-18)2
1125:1123-35:(110+23)-60 205-[1500-(42-2.3)3]