Maths Question:
$\text{Write down the expansion of }{{(1-2x)}^{7}}$
Maths Solution:
$\begin{align} & {{(1-2x)}^{7}}=1{{+}^{7}}{{C}_{1}}(-2x){{+}^{7}}{{C}_{2}}{{(-2x)}^{2}}{{+}^{7}}{{C}_{3}}{{(-2x)}^{3}}{{+}^{7}}{{C}_{4}}{{(-2x)}^{4}}{{+}^{7}}{{C}_{5}}{{(-2x)}^{5}}{{+}^{7}}{{C}_{6}}{{(-2x)}^{6}}+{{(-2x)}^{7}} \\ & {{(1-2x)}^{7}}=1-14x+84{{x}^{2}}-280{{x}^{3}}+560{{x}^{4}}-672{{x}^{5}}+448{{x}^{6}}-128{{x}^{7}} \\\end{align}$
University mathstopic: