Expand (2x-5y)⁷ and find fourth form

Mathematics

1 answer:

elena55 [62]2 years ago

3 0

Step-by-step explanation:

By binomial theorem,

T(r+1) = nCr * a^(r+1) * b^r

Term 4 = 7C3 * (2x)^4 * (-5y)^3 = 35 * (16x^4) * (-125y^3) = -70000x^4y^3.

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