第1个回答 2020-03-01
1. -7 ≤ 2x-1 ≤ 7, -6 ≤ 2x ≤ 8, -3 ≤ x ≤ 4, 又 -3 ≤ x ≤ 3, 则 -3 ≤ x ≤ 3。
2. 0 < 2^x <1 , x∈ (-∞, 0)
3. y = 10^(x+1) - 1, 10^(x+1) = y+1, x = lg(y+1)-1, 反函数 y = lg(x+1)-1, x > -1.
4. ln(x^2+y) = yx^3+sinx, x = 0 时, y = 1,两边对 x 求导,得
(2x+y')/(x^2+y) = y'x^3 + 3x^2y+cosx
x = 0 ,y = 1 代入 得 y'(0) = 1
5. y = ln(tanx) + e^√x, y' = (secx)^2/tanx + e^√x/(2√x) = 2/sin2x + e^√x/(2√x)