I really don't understand why you keep saying there is no unknown. i is the rate of interest, which is the unknown variable.
I don't know how I can make it plainer than that?
Ouch, I wasn't expecting that, ugg!
For (a) what I meant was to make 5(1+i)^8 + 10(1+i)^4 = 3 into a quadratic in x=(1+i)4 so: 5x2+10x - 3 = 0. The numbers are not correct, but the form is.
Thanks for your reply.
Homework Statement
I'm taking a math of investment and credit course, in this case, solving for i which is the interest rate.
My question is: is it possible to "ln both sides" of an equation? Like in (b) below, I know I could say y*ln(1+i) = ln(3).
Homework Equations
(a) 5(1+i)^8 +...
try this instead: (regard this as long division, not a square root!)
2x-1 \sqrt{8x^3+0x^2+0x-1}
And remember, whatever you get in the end, your derivative has a discontinuity at x=1/2!
And don't forget to use the chain rule on the second part. You'll end up with an equation that involves both f(x) and f'(x). At this point, sub in x=1 and f(1)=2 and solve for f'(x).
If the question is supposed to be x²+y²-4x+7y = 15 then I believe that your answer for y' is incorrect.
Note that your original equation is that of a circle which has been shifted. To write it in standard form, (x-a)²+(y-b)²=c² you can complete the square (I'm getting to a nice geometrical...