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Here is an example in my book...

(2-3x^2)(1+2x)^8 = 2(1+2x)^8 - 3x^2(1+2x)^8

The general term in the expansion of (1+2x)^8 is

C(8,k)(2x)^k

Therefore, the term containing x^6 in the expansion of (2-3x^2)(1+2x)^8 is

2(C(8,6))(2x)^6 - 3x^2(C(8,

The coefficient is 244

Where the heck did these

**Determine the coefficient of x^6 in the expansion of**

(2-3x^2)(1+2x)^8(2-3x^2)(1+2x)^8

(2-3x^2)(1+2x)^8 = 2(1+2x)^8 - 3x^2(1+2x)^8

The general term in the expansion of (1+2x)^8 is

C(8,k)(2x)^k

Therefore, the term containing x^6 in the expansion of (2-3x^2)(1+2x)^8 is

2(C(8,6))(2x)^6 - 3x^2(C(8,

**4**))(2x)^**4**= 2(2^6)(C(8,6))(x^6) - 3(2^**4**)(C(8,**4**))(x^6) = 224x^6The coefficient is 244

Where the heck did these

**4's**come from??? Shouldn't they be**6's**or am I missing something?
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