+217 What is the coefficient of $x$ in $(x^3 + x^2 + x + 1)(x^4 - 8x^3 + 17x^2 - 23x + 14)$?
+1257
Every item in the first term is multiplied with every item in the second term.
Pick out the items that, when multiplied, result in an "x" coefficient product.
(x3 + x2 + x + 1) • (x4 – 8x3 + 17x2 – 23x + 14) gives you + 14x
(x3 + x2 + x + 1) • (x4 – 8x3 + 17x2 – 23x + 14) gives you – 23x
add them together for the final value – 9x
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