A positive natural no is 6 less then its square. Cube of the no is

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21 Sep 2010 Natural number

A positive natural no is 6 less then its square. Cube of the no is

OPtion

1) 8
2) 64
3) 125
4) 216
5) 343
6) 512
7) 729
8) 1331
9) 1000
10) 27

Solution

According to given condition
x2 – 6 = x
x2 – x – 6 = 0
(x – 3)(x + 2) = 0
x = 3, - 2

Correct Option: 10 Best Solution (21)

CT.Subbu Lakshmi   13 years AGO

x^2 - x = 6 , x = 3 , x^3 = 27

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Karthik Pandiyan   13 years AGO

Let the number be x
given that x=x^2-6
x^2-x-6=0
x=3 or x=-2
given that number is positive hence x=3
cube of the number is 27

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C.T.Narayanan   13 years AGO

x^2 - x = 6 , x = 3 , x^3 = 27

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Narayanan   13 years AGO

x^2 - x = 6 , x = 3 , x^3 = 27

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CT   13 years AGO

x^2 - x = 6 , x = 3 , x^3 = 27

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Janani   13 years AGO

x^2 - x = 6 , x = 3 , x^3 = 27

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midhun prakash   13 years AGO

3 is the number

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Tridib Das   13 years AGO

X^2 - 6 = x
or, X^2 - 3x + 2x - 6 = 0
or, (x - 3)(x + 2) = 0
or, x = 3
Therefore, x^3 = 27.

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Bawa   13 years AGO

3= 3^2-6; 3^3=27

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susmit   13 years AGO

x*x - 6 =3. so x = 3 and x*x*x = 27

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Mayur   13 years AGO

3^3=27

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Pargat Pal Singh   13 years AGO

A positive natural no (3) is 6 less then its square (9). Cube of the no is 27.

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Inder   13 years AGO

3^3=27

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Achelal Sharma   13 years AGO

the number is 3
it is 6 less than 9 so the cube is 27
x=x2-6

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Gunaseelan   13 years AGO

GIven n+6=n*n;
n^2-n-6=0;
(n-3)(n+2)=0;
n=3,-2;
there fore n^3=27

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PADMASHREE   13 years AGO

9-6=3
3*3*3=27, option 10

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A J V   13 years AGO

Let the natural no. is x. Now, sq(x)-6=x ---> sq(x)-x-6=0 ---> (x-3)(x+2)=0 ---> x=3 or -2. ---> Therefore, cubic sq of x=3*3*3=27.

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SUDESHNA SEN   13 years AGO

Let the positive natural number be x.
Then, x^2-x=6,
or, x^2-x-6=0,
or, x^2+2x-3x-6=0,
or, x(x+2)-3(x+2)=0,
or, (x+2)(x-3)=0,
or, x=-2,3.
Since, x is a positive natural number, so x=3 and x^3= 3^3=27..... Option 10)

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sanjay   13 years AGO

Let the positive natural number be x.
Then, x^2-x=6,
or, x^2-x-6=0,
or, x^2+2x-3x-6=0,
or, x(x+2)-3(x+2)=0,
or, (x+2)(x-3)=0,
or, x=-2,3.
Since, x is a positive natural number, so x=3 and x^3= 3^3=27..... Option 10)

Like? Yes (1) | No   

~Sandeep~   13 years AGO

x^2-6=x => x=3 => x^3 =27

Like? Yes (1) | No   

kamal   13 years AGO

Let the positive natural number be x.
Then, x^2-x=6,
or, x^2-x-6=0,
or, x^2+2x-3x-6=0,
or, x(x+2)-3(x+2)=0,
or, (x+2)(x-3)=0,
or, x=-2,3.
Since, x is a positive natural number, so x=3 and x^3= 3^3=27..... Option 10)

Like? Yes (1) | No