IB HL Maths - Algebra Question

It's part (bii) that I am stuck with.

a) Expand (2a+1)(3-a)
b) Solve:
i) log(2x-5) + log(x) = log3
ii) 2*3^(2x-1) - 5*3^(x-1) - 1 = 0

Reply 1

alow

What work have you done so far?

(also you're more likely to get answers if you post in the maths subforum)

Reply 2

username1036370

Original post by 2012studious

It's part (bii) that I am stuck with.

a) Expand (2a+1)(3-a)
b) Solve:
i) log(2x-5) + log(x) = log3
ii) 2*3^(2x-1) - 5*3^(x-1) - 1 = 0

Also the entirety of this question, also Algebra:

a) If log(a-b) = log a – log b, find an expression for a in terms of b, stating any restrictions on b.

b) If a^2 + b^2 – 2ab = 4 and ab = 4, where a>0, b>0, find the value of 2log20(a+b)

That’s log base 20, but I can’t represent that on my keyboard.

Reply 3

username1036370

Original post by alow

What work have you done so far?

(also you're more likely to get answers if you post in the maths subforum)

I'll post there, too! And what I've done so far is completely solve the first two questions, that is a and bi. Those were straight foward, and I realize that bii should link somehow, but the answer key is throwing me off and I can't manipulate the question very well. :/