Помогите, пожалуйста, срочно надо!!!!!!!!!!

1.
1) Фиксируем x. y(x) = x? + 4x — 6
2) Даём приращение аргументу. y(x + ?x) = (x + ?x)? + 4(x + ?x) — 6 = x? + 2x?x + ?x? + 4x + 4?x — 6
3) Находим приращение функции. ?y = y(x +

?x) — y(x) = x? + 2x?x + ?x? + 4x + 4?x — 6 — x? — 4x + 6 = 2x?x + ?x? + 4?x
4) Составляем отношение ?y/?x.

?y/?x = (2x?x + ?x? + 4?x)/?x = 2x + ?x + 4
5) Находим предел:
$\lim_{\Delta x \to 0} (2x + \Delta x + 4) = 2x+4$

2.
f(x)= 2x? — x? + 4x — 2
f'(x) = 6x? — 2x + 4
f'(2) = 6 * 4 — 2 * 4 + 4 = 24 — 8 + 4 = 20

3.
f(x) = 2? * log?x
f'(x) = 2? * ln2 * log?x + 2? * 1/xln2 = 2?(ln2*log?x + 1/xln2) = 2?(lnx + 1/xln2)
f'(1) = 2(ln1 + 1/ln2) = 2(0 + 1/ln2) = 2/ln2

4.
f(x) = (x? — 5)/(x? — 1)
f'(x) = (2x(x? — 1) — 2x(x? — 5)) / (x? — 1)? = (2x? — 2x — 2x? + 10x) / (x? — 1)? = 8x/(x?-1)?
f'(0) 0/(0-1)? = 0

5.
f(x) = x^(1/8)
f'(x) = 1/8 * x^(1/8-1) = 1/8 * x^(-7/8)
$f'(7) = \frac{1}{8} * 7^{- \frac{7}{8} }= \frac{1}{8} * \frac{1}{7} ^{ \frac{7}{8} }= \frac{1}{8} \sqrt[8]{(\frac{1}{7}) ^7}$