The sum of three consecutive natural numbers is less than 11. Such a natural array has () A. Group 1 B. group 2 C. group 3 d. group 4

The sum of three consecutive natural numbers is less than 11. Such a natural array has () A. Group 1 B. group 2 C. group 3 d. group 4

Let the minimum natural number be x, x + X + 1 + X + 2 ＜ 11x ＜ 223. X can be 0 or 1 or 2. So there are three groups. So choose C

Given the m power of 2 = 3, the n power of 4 = 5, find the 2m-6n + 1 power of 2
Such as the title

2^(2m-6n+1)
=2*(2^m)^2/2^6n
=2*3^2/(4^n)^3
=2*9/5^3
=18/125

The real numbers a and B satisfy b > a > E. e is the base of natural logarithm

Consider the function f (x) = LNX / X (x > e)
f'(x)=(1/x * lnx)'=lnx*(-1/x^2)+1/x * 1/x
=-(lnx-1)/x^2
When x > e, LNX > 1 f '(x) e, f (x) is a decreasing function
Therefore, given b > a > e, f (b) LNB / BB ^ a

A's Square - B's square of a - AB + A + B's square of B

(A & # 178; - B & # 178;) of (A & # 178; - AB) + (a + b) of B
=[(a + b) (a-b)] of [a (a-b)] + (a + b) of B
=(a + b) of a + (a + b) of B
=(a + b) of (a + b)
=1

(ab-b Square) (a square AB)
Simplification

Original formula = B (a-b) · a (a-b)
=ab(a-b)²
=ab(a²-2ab+b²)
=a³b-2a²b²+ab³

Given a + B = 2, ab = 1 / 2, find 1 / 2 (a-b) square

(a-b)²
=(a+b)²-4ab
=2²-4×1/2
=2
The original formula = 2 / 2 = 1

Given a + B = 2, ab = 1, then the value of A-Square and b-ab-square

(a-b)²=(a+b)²-4ab=2²-4x1=0
So we can get: A-B = 0
a²b-ab²
=ab(a-b)
=1x0
=0

Given a + B = 2, ab = 4, find the square of a + the square of B

Square of a + square of B
=(a+b)²-2ab
=2²-2*4
=-4

If A-B = 7, ab = 2, find the square of a + B and the square of (a + b)!

Square of a + square of B
=(a-b)^2+2ab
=7^2+2*2
=43
The square of (a + b)
=a^2+b^2+2ab
=43+2*2
=47

Given a + B = 6, ab = 4, find the sum of squares of ab
Given a + B = 6, ab = 4, find the square of a plus the square of B

a^2+b^2
=(a+b)^2-2ab
=6^2-2*4
=28
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