Please give a counter example to show that the following proposition is false 1. Equal angles are right angles 2, if a + B = 0, then a = 0, B = 0 3. If ∠ 1 is greater than ∠ 2, then ∠ 1 is an obtuse angle

Please give a counter example to show that the following proposition is false 1. Equal angles are right angles 2, if a + B = 0, then a = 0, B = 0 3. If ∠ 1 is greater than ∠ 2, then ∠ 1 is an obtuse angle

1 two flat angles
2 A + B = 0 AB is the opposite number a = - 3 B = 3
3 ∠1>∠2 ∠1=80,∠2=60

Give counter examples that can explain false propositions
The difference between an obtuse angle and an acute angle must be an acute angle

120 degrees - 10 degrees = 110 degrees, obtuse angle

The inverse proposition of the proposition "if two real numbers are equal, then their squares are equal" is______ Is it true______ ．

Because the converse proposition of "if two real numbers are equal, then their squares are equal" is "if two real numbers are equal, then the two real numbers are equal". For example, two opposite numbers are equal, but the two numbers are not equal, so it does not hold

If a is a rational number, then a is a real number_____ His converse proposition is_____ Yes_____ (fill in "true" or "false") proposition

If a is a rational number, then a is a real number__ True___ proposition
His converse proposition is__ If a is a real number, then a is a rational number___ Yes__ False___ proposition

F (x) = x & # 178; + ax + B, G (x) = x & # 178; - X-2, when x approaches 2, the limit of F (x) / g (x) is equal to 2, and the constants a, B are obtained

f(x)/g(x)=（x²+ax+b）/（x²-x-2）=（x²+ax+b）/[（x-2）（x+1）]
When x approaches 2, the limit of G (x) is equal to 0; therefore, if the limit of F (x) / g (x) exists,
Then (X & # 178; + ax + b) = (X-2) (x + C) -- - (1)
Then f (x) / g (x) = (x + C) / (x + 1);
When x approaches 2, the limit of F (x) / g (x) is equal to 2, then C = 4, substituting (1),
A = 2, B = - 8

Function y = x to the power of a, a is a constant, what is its domain of definition?

The domain D of power function y = x ^ a depends on what number a is
A is a positive integer, d = all sets of real numbers R,
A is a negative integer, d = {x | x ≠ 0, X ∈ r},
A is a positive reduced fraction with even denominator, d = {x | x ≥ 0, X ∈ r},
A is a negative reduced fraction with even denominator, d = {x | x > 0, X ∈ r},
A is a positive reduced fraction with odd denominator, d = R,
A is a negative reduced fraction with odd denominator, d = {x | x ≠ 0, X ∈ r},
A is a positive irrational number, d = {x | x ≥ 0, X ∈ r},
A is a negative irrational number, d = {x | x > 0, X ∈ r},

Let me give you this birthday present?

it is no better than giving you a birthday gift by me

How many Mu is it 20 meters long and 13 meters wide?
Specific algorithm is? For example, 135 meters long.. 255 meters wide is equal to how many acres? How to calculate? More specific

1 mu = 666.67 square meters
20 * 13 = 260 M2 = 0.39 Mu
135 * 255 = 34425 M2 = 51.64 Mu

The number of integer solutions (x, y) of the equation XY + Y-9 = 0 is ()

There are six
XY + Y-9 = 0 can be transformed into XY + y = 9, (x + 1) y = 9
Because it is an integer solution, it is only 1 times 9, and the result is (0,9) (8,1)
-1 times - 9, the result is (- 2, - 9) (- 10, - 1)
3 times 3, the result is (2,3)
-3 times - 3, the result is (- 4, - 3)
The answer is right,

English words from January to December

January
February
March, Marcy
April April
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July, July
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December