Differentiate `y = 2e^(-3x)` with respect to `x`. (1 mark)
--- 3 WORK AREA LINES (style=lined) ---
Aussie Maths & Science Teachers: Save your time with SmarterEd
Differentiate `y = 2e^(-3x)` with respect to `x`. (1 mark)
--- 3 WORK AREA LINES (style=lined) ---
`-6e^(-3x)`
`y` | `=2e^(-3x)` | |
`dy/dx` | `=-3 xx 2e^(-3x)` | |
`=-6e^(-3x)` |
Let `f(x) = e^(x^2)`.
Find `f^{\prime} (3)`. (3 marks)
--- 4 WORK AREA LINES (style=lined) ---
`6e^9`
`text(Using Chain Rule:)`
`f^{\prime} (x)` | `= 2xe^(x^2)` |
`f^{\prime} (3)` | `= 2 (3) e^((3)^2)` |
`= 6e^9` |
For `f(x) = log_e (x^2 + 1)`, find `f^{\prime}(2)`. (2 marks)
--- 3 WORK AREA LINES (style=lined) ---
`4/5`
`text(Using Chain Rule:)`
`f ^{\prime}(x)` | `= (2x)/(x^2 + 1)` |
`:. f ^{\prime}(2)` | `= (2(2))/(2^2 + 1)` |
`= 4/5` |
Let `y=ln(3x^3 + 2)`.
Find `dy/dx`. (2 marks)
--- 5 WORK AREA LINES (style=lined) ---
`2e^x(e^x + 1)`
`y` | `=ln(3x^3 + 2)` | |
`(dy)/(dx)` | `=(3*3x^2)/(3x^3 + 2)` | |
`=(9x^2)/(3x^3 + 2)` |
Evaluate `f^{\prime}(1)`, where `f: R -> R, \ f(x) = e^(x^2-x + 3)`. (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
`e^3`
`f(x)` | `= e^(x^2-x + 3)` |
`f^{\prime}(x)` | `= (2x-1)e^(x^2-x + 3)` |
`f^{\prime}(1)` | `= (2-1)e^(1-1 + 3)` |
`= e^3` |
Differentiate `(e^x + x)^5`. (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
`5(e^x + 1)(e^x + x)^4`
`y` | `= (e^5 + x)^5` |
`(dy)/(dx)` | `= 5(e^x + x)^4 xx d/(dx)(e^x + x)` |
`= 5(e^x + x)^4 xx (e^x + 1)` | |
`= 5(e^x + 1)(e^x + x)^4` |
Differentiate `(e^x + 1)^2` with respect to `x`. (2 marks)
--- 2 WORK AREA LINES (style=lined) ---
`2e^x(e^x + 1)`
`y` | `= (e^x + 1)^2` | |
`(dy)/(dx)` | `= 2(e^x + 1)^1 xx d/(dx) (e^x + 1)` | |
`= 2e^x(e^x + 1)` |
Let `f(x) = x^2e^(5x)`.
Evaluate `f^{\prime}(1)`. (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
`7e^5`
`text(Using Product Rule:)`
`(fg)^{\prime}` | `= f^{\prime}g + fg^{\prime}` |
`f^{′}(x)` | `= 2xe^(5x) + 5x^2 e^(5x)` |
`f^{′}(1)` | `= 2(1)e^(5(1)) + 5(1)^2 e^(5(1))` |
`= 7e^5` |
For `y = e^(2x) cos (3x)` the rate of change of `y` with respect to `x` when `x = 0` is
`B`
`y` | `= e^(2x) cos (3x)` |
`dy/dx` | `=e^(2x) xx -3sin(3x) + 2e^(2x) xx cos (3x)` |
`=e^(2x)(-3sin(3x) + 2cos(3x))` |
`text(When)\ \ x = 0,`
`dy/dx= 2`
`=> B`
The derivative of `log_e(2f(x))` with respect to `x` is
`A`
`text(Chain Rule:)`
`text(If)\ \ h(x)` | `= f(g(x))` |
`h′(x)` | `= f′(g(x)) xx g′(x)` |
`d/(dx)(log_e(2f(x)))` | `= 1/(2f(x)) xx 2f′(x)` |
`= (f′(x))/(f(x))` |
`=> A`