Scientific counting approximate significant number What's the exact decile of 0.00000007? How many significant numbers are there
To be precise to the tenth is like this: 12345 becomes the fourth power of 1.2 * 10
So your question should be 0.7 * 10 seventh power, the number of significant digits is naturally 2, because 07 is two digits
A + 2B = 0 a ^ 3 + 2Ab (a + b) + 4B ^ 3-8 (^ is a power)
A ^ 2-2ab + 2B ^ 2-4b + 4 = 0 to the - B power of (a-5)
A ^ 2 is the square of A
a^2-2ab+2b^2-4b+4=0
(a-b)^2+(b-2)^2=0
a=b,b=2
So, a = b = 2
The - B power of (a-5)
=(2-5)^(-2)
=(-3)^(-2)
=1/9
From the table, you can find out what is the rule of the number of single digits of power n of 2? What is the number of single digits of power 2005 of 2
The single digits of the n-th power of 2 are 2,4,8,6,2... Cycles
The remainder of 2005 / 4 = 1
So, the single digit of 2 in 2005 is 2
Under what circumstances can Newton Leibniz formula not be used for definite integral of higher numbers?
Why can't we use that formula
Operation of power
2X + 1 power of 2 + x power of 4 = 48
The X + 1 power of 3, the x power of 2 minus the x power of 3, the X + 1 power of 2 = the square of 2, the square of 3
Find X in the above formulas
2X + 1 power of 2 + x power of 4 = 48
2^(2x+1)+4^x=48,
2*2^2x+4^x=48,
2*4^x+4^x=48,
3*4^x=48,
4^x=16,
x=2,
The X + 1 power of 3, the x power of 2 minus the x power of 3, the X + 1 power of 2 = the square of 2, the square of 3
3^(x+1)*2^x-3^x*2^(x+1)=2^2*3^2
3*3^x*2^x-2*3^x*2^x=36,
3^x*2^x=36,
6^x=36,
x=2
The operation of power,
If 2 ^ m = x, then 4 ^ m=
If x = 2 ^ m + 1, 3 + 4 ^ m, then y is expressed by the formula containing X
Compare size
3^555
4^444
5^333
12 if 2 ^ m = x, then 4 ^ m = x ^ 2
2.X = 2^m +1 2^m = x-1
y=3+4^m = 3+ (2^m)^2 = 3+(x-1)^2 = X^2 - 2x + 4
Y = X^2 - 2 x + 4
3.3^555=(3^5)^111
4^444=(4^4)^111
5^333=(5^3)^111
∵3^5=243,4^4=256,5^3=125
∴(5^3)^111<(3^5)^111<(4^4)^111
∴5^333<3^555<4^444
On the operation of power
10=2x5,10=(2x5)²
100=4x5=2²x5²,100=10²=(2x5)²
1000=8x125=2³x5³,1000=10³=(2x5)³
……
What rules do you find in it?
Exponents are constant, bases are multiplied
The sum of 27 continuous natural numbers is 1998, and the smallest one is 1998______ .
According to the meaning of the question: the middle number is: 1998 △ 27 = 74, that is, the fourteenth number is 74, because the fourteenth number is 14-1 = 13 larger than the smallest number, so the minimum natural number is: 74-13 = 61
If the sum of three continuous natural numbers is 27, then the sum of squares of these three numbers is 27______ .
27 △ 3 = 9; 9-1 = 8; 9 + 1 = 10; 82 + 92 + 102, = 64 + 81 + 100, = 245; so the answer is: 245