+118677 
+1313 
+118677 Stu:[/quote]1. Differentiate (use appropiate notation)
a) y = x9
y'=9x8
b) f(x)=5x3 - 3x + 6
f'(x)=15x2 -3
c) y = 4x-5
y'=20x4 (You could have used dy/dx= but y' is fine as well - But it should have been y' = -20x-5-1 = ?) Can you finish this please Stu
2. d/dx (-12x)
f"(x) = -12 Not f"(x) You only use " when you differentiate twice.
The best answer would be d/dx (-12x) = -12
3. differentiate
a) y = (2x+3)4
y' = 4*(2x+3)3*2 That is correct but you can simplify this answer.
b) f(x) = x2 ( 2x+3)4
f'= 2x+4*(2x+3)3*2
b) f(x) = x2 ( 2x+3)4
For this question you need to use the product rule. If y=uv then y'=uv' + vu'
u=x2 so u'=2x
v=(2x+3)4 so v'=4(2x+3)3*2 = 8(2x+3)3
Now you have to substitute those values into the formula and simplify the answer.
Could you try doing that please Stu?
Thanks,
Melody.
