I shouldn't be wrong!

It should be -2. Why did they sum the 20? 20 is a constant, not a coefficient, right? And also, the solution has one more error also.. Look at the part when the $x^2$ is multiplied with the function inside the bracket besides it.

Edit: I know that after 20 there is a variable of x which has power of 0. But, isn't it still a constant?

Easy Math Editor

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Comments

I know that after 20 there is a variable of x which has power of 0. But, isn't it still a constant?

Yes, it is a constant. And it is the co-efficient of $x^0$ .

Siam Habib - 7 years, 1 month ago

The coefficient of the constant term $20 x^0$ is 20.

Thanks for pointing out the typo in the solution. I've edited it. It should say -3 instead of -5 throughout, and in the second solution $31$ should be replaced by $3 \times 1$ . The final answer of 18 is still correct.

Calvin Lin Staff - 7 years, 1 month ago

thanks for the correction. I have one more prob, where should I report? by note or?

Eka Kurniawan - 7 years, 1 month ago

You can click on the "Request Clarification or Dispute" link placed at the bottom.

Imgur Imgur

I noticed that after you view solutions, the link is not available. I'd get the link to be displayed. In the meantime, you can send me an email with the screenshot, and I'd check it out. Thanks!

Calvin Lin Staff - 7 years, 1 month ago

@Calvin Lin – what's your e-mail?

Eka Kurniawan - 7 years, 1 month ago

@Eka Kurniawan – Calvin @ brilliant.org

(no spaces)

Calvin Lin Staff - 7 years, 1 month ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$