Help with Binomial Expansion Question | Mathematics | Page 1

vague parrot Sep 13, 2022, 10:15 AM

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Can anyone help me with part A?

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I tried working it out but I did something wrong

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this is the answer

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rn_image_picker_lib_temp_b2e7c0b6-aec1-43cb-8282-6de712c645e6.jpg

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where did 7 choose 2 come from??

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ive done something very wrong lol

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okay so its y^r not y^n

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i am stupid

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let me try this

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okay i still dont know where the 7 choose 2 comes from

thick wasp Sep 13, 2022, 10:55 AM

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vague parrot okay i still dont know where the 7 choose 2 comes from

It should be 7Cr.

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It's a typo.

vague parrot Sep 13, 2022, 10:55 AM

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breh

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alright thanks

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do you know how to do part b?

thick wasp Sep 13, 2022, 10:57 AM

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Well, 1/x = x^(-1), so we want to find the rth term when 14 - 5r = -1.

vague parrot Sep 13, 2022, 11:00 AM

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wait sorry why do we do that?

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what does the rth term tell us?

thick wasp Sep 13, 2022, 11:05 AM

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... what is the question asking?

vague parrot Sep 13, 2022, 11:05 AM

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find the value of d with the coefficient of 1/x being - 70000

thick wasp Sep 13, 2022, 11:07 AM

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And what's the power of x?

vague parrot Sep 13, 2022, 11:08 AM

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hihi sorry its alright I managed to ask my teacher about it

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thanks for your help though :)

#Help with Binomial Expansion Question