Well, darling, to find the units digit of 2 to the 57th power, you just need to look for a pattern. The units digit of powers of 2 cycles every 4 powers: 2, 4, 8, 6. So, 57 divided by 4 leaves a remainder of 1, meaning the units digit of 2 to the 57th power is 2. Hope that clears things up for you, sugar!
When the units digit equals the tens digit then the sum of the digits of a 2 digit number is double the units digit. In each tens range above 50, numbers below this critical point meet the requirement, numbers above this critical point have a sum LESS than double the units digit. The applicable numbers are 51-54 (4), 61-65 (5), 71-76 (6), 81-87 (7) and 91-98 (8). Then there are 4 + 5 + 6 + 7 + 8 = 30 qualifying numbers.
Any two digit number in which: (a) the units digit is not 0, and (b) the two digits are different will form a new 2-digit number when the digits are interchanged.
The nth triangular number is given by ½ × n × (n+1)→ the 5857th triangular number is ½ × 5857 × 5858 = 17,155,153, so its units digit is a 3.------------------------------------------------------------Alternatively,If you look at the units digits of the first 20 triangular numbers they are {1, 3, 6, 0, 5, 1, 8, 6, 5, 5, 6, 8, 1, 5, 0, 6, 3, 1, 0, 0}At this stage, as we are only concerned with the units digit, as we now have a 0 for the units digit, when 21 is added it is the same as adding 1 to 0 to give a 1, for the 22nd triangular number, we are adding 2 to the 1 to give 3, and so on - the sequence of 20 digits is repeating.To find the units digit of the nth triangular number, find the remainder of n divided by 20 and its units digit will be that digit in the sequence (if the remainder is 0, use the 20th number). To find the remainder when divided by 20 is very simple by looking at only the tens digit and the units digit:If the tens digit is even (ie one of {0, 2, 4, 6, 8}), the remainder is the units digitIf the tens digit is odd (ie one of {1, 3, 5, 7, 9}), the remainder is the units digit + 10.5857 ÷ 20 = ... remainder 17; the 17th digit of the above sequence is a 3, so the units digit of the 5857th triangular number is a 3.This trick can be used for much larger triangular numbers which calculators cannot calculate exactly using the above formula. eg the units digit of the 1234567890123456789th triangular number is... 1234567890123456789 ÷ 20 = .... remainder 9, so this triangular number's units digit is the 9th digit of the above sequence which is a 5.
For the tens digit to be a prime number then it must equal 2, 3, 5 or 7. There are four 3-digit prime numbers that fit the above condition and also have the tens and units digits forming a 2-digit prime number. 131, 137, 173, 179. The person supplying the question may like to sum the various combinations.
Because the number is the square of its units digit, it must be the square of a number between 1 and 9. Look at the squares of the first nine numbers.The square of 1 is 1.The square of 2 is 4.The square of 3 is 9.The square of 4 is 16.The square of 5 is 25.The square of 6 is 36.The square of 7 is 49.The square of 8 is 64.The square of 9 is 81.Of these numbers, 1, 25, and 36 are squares of their units digit.
Power 2: units digit 9. Multiply by 49 again to get power 4: units digit 1. So every 4th power gives units digit 1. So 16th power has units digit 1, so the previous power, the 15th must have units digit 3.
6.
The unit's digit in the expansion of 2 raised to the 725th power is 8. This can be determined by using the concept of the "unit's digit law". This law states that the units digit of a number raised to any power is the same as the units digit of the number itself. In this case, the number is 2, which has a units digit of 2, so the units digit of 2 to the 725th power is also 2. However, this is not the final answer. To get the unit's digit of 2 to the 725th power, we must use the "repeating pattern law". This law states that when a number is raised to any power, the unit's digit will follow a repeating pattern. For 2, this pattern is 8, 4, 2, 6. This means that the units digit of 2 to any power will follow this pattern, repeating every 4 powers. So, if we look at the 725th power of 2, we can see that it is in the 4th cycle of this repeating pattern. This means that the units digit of 2 to the 725th power is 8.
8.796093e+12= 2 to the 43rd power
Expressed in numerical form, 248 = 281474976710656 - the units digit is therefore 6. With the exception of 20 = 1. the units digit of successive powers of 2 runs 2, 4, 8, 6... continuously - therefore, an exponent which is a multiple of 4 will have a units digit of 6.
819 = 144115188075855872 The number in the units column is therefore 2.
To find the units digit of a number raised to a power, we can look for patterns in the units digits of the powers of that number. For 2, the units digits of the powers cycle in a pattern: 2, 4, 8, 6. Since 2011 is 3 more than a multiple of 4 (2011 = 4 * 502 + 3), the units digit of 2 to the power of 2011 will be the fourth number in the cycle, which is 6.
Scientific notation: 1.441151881x1017
To find the units digit of 8 to the power of 50, we need to look for a pattern in the units digits of powers of 8. The units digit of powers of 8 cycles in a pattern: 8^1 = 8, 8^2 = 4, 8^3 = 2, 8^4 = 6, and so on. Since the cycle repeats every 4 powers, we can divide 50 by 4 to find that the 50th power will have the same units digit as 8^2, which is 4. Therefore, the units digit of 8 to the power of 50 is 4.
The units digit of 159*445*7762*39 is the units digit of the product of the units digits of the four numbers, that is, the units digit of 9*5*2*9 Since there is a 5 and a 2 in that, the units digit is 0.
When the tens digit is even and the units digit is 0, 4 or 8 or the tens digit is odd and the units digit is 2 or 6.
The last digit of a number raised to a power can be determined by finding a pattern in the units digits of the number's powers. For 2 raised to the power of 1997, the units digit will follow a pattern of 2, 4, 8, 6. Since 1997 is one less than a multiple of 4, the last digit will be 8.