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If in the expansion of (1+x)^m (1-x)^n, ...

If in the expansion of `(1+x)^m (1-x)^n`, the coefficients of `x and x^2` are 3 and -6 respectively, then m is:

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`(1+a_{1} x+a_{2} x^{2}+ldots)(1-p_{1} x+p_{2} x^{2}+ldots)`L
Hence coefficient of `x` will be
=-{p}_{1}+{a}_{1}
`=-\ ^{{n}} {C}_{1}+\ ^{{m}} {C}_{1} `
`={m}-{n} `
`=3 ldots({i})`
Coefficient of `x^{2}` will be
`=p_{2}-a_{1} p_{1}+a_{2} `
...
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