Answer:
32x^3
Explanation:
![(2x+1)^4=(2x)^4+4(2x)^3(1)+6(2x)^2(1)^2+4(2x)(1)^3+(1)^4\\\\=16x^4 +\boxed{32x^3} +24x^2+8x+1](https://img.qammunity.org/2021/formulas/mathematics/college/ojc92ejhbce0022r9w4871ogzjbo4cppx0.png)
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Comment on the question
It is helpful if you designate exponents with a caret (^). We expect the expanded form of (2x+1)4 to be 8x+4. (2x+1)^4 is entirely different. Similarly, 8x3 = 24x, whereas 8x^3 is something else.