simple trick to obtain a cube root of any no.

here for this method you had to remember the cubes of 1to 10 by heart. after that i give a guarantee that now you will able to find the cube root of any no in just 5 seconds

for your help i am giving the cube of 1to 10
1cube:-1
2cube:-8
3cube:-27
4cube:-64
5cube:-125
6cube:-216
7cube:-343
8cube:-512
9cube:-729
10cube:-1000

for finding the cube root of 421875

here above you can observe that the unit place the cubes have all 0-9 no.

you can observe that the cubes of 11to the 99 are only 6 digit answer so the the no which we are going to find a cube is a two digits.

1st step here in the example the unit place no is 5 so lets see the any cubes have 5in its unit place

yes you got that the 5 cube is 125
so the unit place no of our cube is 5

next step to find the tens place no of our cube

for this you have to cut last 3 digit no . of your question i.e in the example
so the remaining no. is 421


lets observe in which cubes between the 421 is
so the 421 is in between of 343 and 512 I.e 7&8cube

now we have to choose a lowest no.
i e 7 (which lies in a tens place)

yo therefore the answer is 75

for the first time you can feel it is difficult but as you practice it it becomes easier and you can find the answers of easily

this method can be used in last minutes of examination where students have to check all there answers

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thank you for giving your precious time

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