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Santanu Sahoo
Subject: Maths
, asked on 27/10/17
In my last doubt, I asked to give a formal proof, for (-)(+)=(-). I was asked by my maths teacher in school, that how when 2 unlike signs are multiplied, why the result is a negative value. Neha ma'am answered this last time, but it was not at all satisfactory.. I wanted one of the formal proofs like Brijendra Pal sir gave me for (-)(-)=(+)..Experts may prefer to that one, to make the answer satisfactory for (-)(+)=(-)...... Shruti ma'am you answered how (-)(-)=(+).....But I asked how (-)(+)=(-)...Hope you got... What I want to ask.. .
Answer
6
Santanu Sahoo
Subject: Maths
, asked on 27/10/17
In my last doubt, I asked to give a formal proof, for (-)(+)=(-). I was asked by my maths teacher in school, that how when 2 unlike signs are multiplied, why the result is a negative value. Neha ma'am answered this last time, but it was not at all satisfactory.. I wanted one of the formal proofs like Brijendra Pal sir gave me for (-)(-)=(+)..Experts may prefer to that one, to make the answer satisfactory for (-)(+)=(-)...
Answer
4
Santanu Sahoo
Subject: Maths
, asked on 26/10/17
I had asked how (-)(+) = (-)? I want a formal proof for this.
This question was asked by my maths teacher in school... But, When I showed this, he asked that how corollary 1 is proving, (-)(+) = (-). He means to say how when 2 different signs are multiplied, how to say that the value is (-)., . Please experts make me understand very specifically, how, (-)(+) = (-), with a formal proof...
Answer
3
Santanu Sahoo
Subject: Maths
, asked on 25/10/17
I had asked that how (-)(+) = (-). Brijendra Pal sir answered this to me.
This was that:
We know that -ab is a unique solution to the equation x + ab =0, therefore it is sufficient yo show that
ab + (-a)b = 0
ab + (-a)b = (a + (-a))b
by the Distributive Property of Real Numbers (Axiom 5A) and
a+(-a) = 0
by Axiom 5A (the existence of Additive Identity).
Therefore,
ab + (-a)b = (a +(-a))b = 0b = 0
and we are done.
The theorem above give to 2 corollaries.
Corollary 1
For any number b, (-1)b = -b
If we take a = -1, then (-1)b = -(1b) =-b by the existence of multiplicative identity (Axiom 5M).
(-1)(-1) = 1
I am able to understand what he wrote, but, I am still not getting the Corollary 2 and my teacher also asked, how the Corollary 2 is proved. Please I want this soon because it is asked by my Maths teacher in school.
Please experts get into this.
Answer
1
Santanu Sahoo
Subject: Maths
, asked on 24/10/17
I had asked that how: (-)(-)= (+). I saw that in that, (-) (+) = (-)... Prove how(-) (+) = (-). I am asking this again. Sorry for the impatience. I know experts have to see quite a many questions globally, so there may be some time taken to answer the questions.. So, just see to this a little soon.
Answer
7
Santanu Sahoo
Subject: Maths
, asked on 23/10/17
I had asked that how: (-)(-)= (+). I saw that in that, (-) (+) = (-)... Prove how(-) (+) = (-)
Answer
7
Santanu Sahoo
Subject: Maths
, asked on 22/10/17
Is there formal proof for (-)(-)= (+). Please help me to get the answer. This, has been ask by my Maths teacher in school.
A expert answered this, but, he told me that how (-1) x (-1) = 1. Actually, it has some expressions like "-(-1) = 1.
Here we have (-)(-).. without proof.
So, please be a little specific.
Answer
3
Santanu Sahoo
Subject: Maths
, asked on 21/10/17
3 of my questions are not answered yet. I referring to the last 3 questions I have asked yesterday (not this). I know that I should give it in the feedback. But, I'm on Android. Please see to this.
Answer
5
Kuldeep Kaur
Subject: Maths
, asked on 21/10/17
(-64)x(-9)+64
Answer
6
Santanu Sahoo
Subject: Maths
, asked on 20/10/17
Is there a formal proof for (−1)×(−1)=1. If yes, then answer. Please don't copy from internet or Don't tell that (-)*(-)=+ as I have asked to tell the formal proof.
Answer
1
Santanu Sahoo
Subject: Maths
, asked on 20/10/17
Q. Prove : (- 1)
×
(- 1) = 1. Please experts, answer this, according to the context or reference given in the picture.
Euler in his Ankitung zur Algebra(1770), was one of the first mathematicians to attempt to prove (- 1)
×
(- 1) = 1
Answer
7
Shivam Gupta
Subject: Maths
, asked on 20/10/17
Three particles having their masses in the ratio 1:3:5 are kept at the vertices of a triangle ABC. Coordinates of A,B and C are (9,-3),(3,4) and (0,0). Find the coordinates of the centre of mass.
Answer
1
Saumya Jadav
Subject: Maths
, asked on 1/10/17
what is the result of this: (-2)+(-3)*(-3)+(-4)
Answer
6
Seven Live
Subject: Maths
, asked on 19/9/17
Define cake?
Answer
2
Sagar
Subject: Maths
, asked on 18/9/17
write down 5 pairs of integers whose product is 20
Answer
4
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What are you looking for?
This question was asked by my maths teacher in school... But, When I showed this, he asked that how corollary 1 is proving, (-)(+) = (-). He means to say how when 2 different signs are multiplied, how to say that the value is (-)., . Please experts make me understand very specifically, how, (-)(+) = (-), with a formal proof...
This was that:
We know that -ab is a unique solution to the equation x + ab =0, therefore it is sufficient yo show that
ab + (-a)b = 0
ab + (-a)b = (a + (-a))b
by the Distributive Property of Real Numbers (Axiom 5A) and
a+(-a) = 0
by Axiom 5A (the existence of Additive Identity).
Therefore,
ab + (-a)b = (a +(-a))b = 0b = 0
and we are done.
The theorem above give to 2 corollaries.
Corollary 1
For any number b, (-1)b = -b
If we take a = -1, then (-1)b = -(1b) =-b by the existence of multiplicative identity (Axiom 5M).
(-1)(-1) = 1
I am able to understand what he wrote, but, I am still not getting the Corollary 2 and my teacher also asked, how the Corollary 2 is proved. Please I want this soon because it is asked by my Maths teacher in school.
Please experts get into this.
A expert answered this, but, he told me that how (-1) x (-1) = 1. Actually, it has some expressions like "-(-1) = 1.
Here we have (-)(-).. without proof.
So, please be a little specific.
Euler in his Ankitung zur Algebra(1770), was one of the first mathematicians to attempt to prove (- 1) (- 1) = 1