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## Bharat Gupta is teaching live on Unacademy Plus

Bharat Gupta

Engineer by degree Mathematician by Heart. Having 22 years of teaching experience.
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Comments

(5)

U

Unacademy user

Kanchan Chahar

3 years ago

sir kon se month ki h yeh nhi pata chalta or April ki kaha update h

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AC

Arijeet Chatterjee

a year ago

Sir in the last question you have given the sum upto factorial 100... but during solution why have u solved until factorial 4

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Pg

Prateek gupta

a year ago

5 factorial se sabke unit digit zero hota hai (5! = 5×4×3×2×1 =120) to koi matlb nhi lene ka

Pg

Prateek gupta

a year ago

5 factorial se sabke unit digit zero hota hai (5! = 5×4×3×2×1 =120) to koi matlb nhi lene ka

AC

Arijeet Chatterjee

a year ago

My apologies.. I have understood the logic.. U are right sir

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Pranav Sahal

8 months ago

in the last question the unit digit of the power is 1. And when I used to solve it it comes out to be 1^1+2^1+3^1+4^1 =10, for which unit digit is 0. while in the solution given by sir, unit digit comes out to be something else. please help me out with this.

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Rohan kumar

6 months ago

1!=1,2!=2,3!=6,4!=24...so their unit digit sum is 13..unit digit = 3

Pranav Sahal

8 months ago

sir' solution is 1^1+2^1+6^1+4^1 which is 13 and UD is 3.. where does this 6 instead of 3 is there.. this is my doubt.

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AM

Anand Mishra

3 months ago

trailing num ni smjh aaiya phr bta dijiye

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