Question

срочно математика срочно срочно
$f(x)5x ^{7} + 6x ^{4} + 5x \: \: \ \: \: \: \: \: \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: f"(1) =? \: \: \: f"(3) = ?$
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Answer 1

$f(x) = 5 {x}^{7} + 6 {x}^{4} + 5x \\ f'(x) = 7 \times 5 {x}^{6} + 4 \times 6 {x}^{3} + 5 = 35 {x}^{6} + 24 {x}^{3} + 5 \\ f''(x) = 6 \times 35 {x}^{5} + 3 \times 24 {x}^{2} = 210 {x}^{5} + 72 {x}^{2} \\ f''(1) = 210 \times {1}^{5} + 72 \times {1}^{2} = 210 + 72 = 282 \\ f''(3) = 210 \times {3}^{5} + 72 \times {3}^{2} = 210 \times 243 + 72 \times 9 = \\ = 51030 + 648 = 51678$