Wednesday 23 September 2015

Square roots-General mistakes

        1-3=4-6 is it correct? yes it is.

             12_2x[3/2]x1=22-2x[3/2]x2    add [3/2]2 both side on both side

                   12_2x[3/2]x1+[3/2]2=22-2x[3/2]x2+[3/2]2   identified as a2+2ab+b2=[a+b]2

                         [1-3/2]2=[2-3/2]cancel the squares on both sides

                              1-3/2=2-3/2
:        .1=2     is it correct ? Actually where is the mistake?

simply we  cancelled the squares on both sides
But it is not correct.
We don’t forget about + on right hand side or left hand side of the equation.
Don't commit mistakes by forgetting fundamentals.

As above, many examples can be taken as a2_2a[a+b]/2=b2_2b[a+b]/2 both sides we can get -ab on both sides so satisfied the equation.

Take another example
take a=3 and b=4
then a2_2a[a+b]/2=b2_2b[a+b]/2
       32_2x3[[3+4]/2]=42_2x4[3+4]/2
       9-21=16-28
        -12=-12
Equation satisfied

32_2x3[3+4]/2=42_2x4[3+4]/2 add {[3+4]/2}on both sides.
32_2x3[3+4]/2+{[3+4]/2}=42_2x4[3+4]/2+{[3+4]/2}it is in the form of  a2+2ab+b2=[a+b]2
 [3-7/2]2=[4-7/2]2
if cancel the squares on both sides, equation becomes 3=4,which is practically wrong.
3-7/2=-1/2, 4-7/2=1/2, -1/2 is not equal to 1/2 but [-1/2]2=[1/2]2

Square roots Simple method
Any real +ve number in the form of [a+b]2=a2+2ab+b2
+ve numbers are mainly perfect squares and imperfect squares.
step1 identify a number's possibility of perfect square.
All perfect squares have either of the perfect square digit in 1s place as below
i.e 0,1,4,9,6.
256 mayor may not  be perfect square
252 is not perfect square.
456789 mayor may not  be perfect square
789235 is not a perfect square
by this we can estimate a number either chances of perfect square and not.

Finding of Square root of a number

I.e Find the square root of 7225




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