Doubt from Quadratic equations

#1


I have done Q 4 by this method

Is there any beautiful approach other than this

#2

The above is the simplest method. The approach behind the problem is to expand the multiplication.

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#3


Q 7

#4

Is it 7?

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#5

Yes, I am also getting 7
z = 3x, y =0
So, 10x^2<=100
So, |x|<3.16
Therefore, x = all integers between -3 and 3, including both of them

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#6

Answer is 7.

#7

Answer is 7.

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#8

Yeah, it's 7. Thanks to all of you, made a caulation mistake :sob: in my answer.

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#9


Q 5

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#10

Is the answer for 5th question is 0?

#11

Yes, it should be zero.

#12

Yes , it is

#13

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#14

@Abhishek_2021_2 please share your approach

#15

@Shiva_1 Sir , I totally agree with you that it's repeating it's behavior but we can't say that it would not have any root by observation .( May be I am wrong but do you have any example that explains the same case)

#16

You can draw two graphs and see that they don't meet. This is another approach which shows logical proof for my answer.

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#17

Yes, this would be, imo, an easier approach, drawing the the graphs of x^2 + 4x + 3 and -[x].

#18

Yeah , thanks . Sir.

#19

I did it by making graph of fractional part.

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#20


Q 1 and 2