Means log2x3=3log2x If so, then what? I don't understand what the acutal answer is supposed to me? And which rule do I use for the square root of x one? (Sorry for the continuous questions!)
Wondered if you might want to help out again, its fine if you don't
f(x)=x3-x2-7x+c f(4)=0 a) Find C (which I got -20 for) b) Factorise f(x) as the product of a linear factor and a quadratic factor c) hence show that, apart from x=4, there are no real values of x for which f(x)=0
B+C are confusing me. I guessed that I needed to find the quotient using (x-4) and then factorise it using the quadratic formula which didnt work.
Wondered if you might want to help out again, its fine if you don't
f(x)=x3-x2-7x+c f(4)=0 a) Find C (which I got -20 for) b) Factorise f(x) as the product of a linear factor and a quadratic factor c) hence show that, apart from x=4, there are no real values of x for which f(x)=0
B+C are confusing me. I guessed that I needed to find the quotient using (x-4) and then factorise it using the quadratic formula which didnt work.
Not sure what it's asking me to do now:/
You know that f(4)=0 so (x-4) is a factor (from factor theorem).
f(x)=(x−4)(Ax2+Bx+C)
You should be able to write down the values of A and C immediately and figure out B (expand the brackets and equate coefficients if you need to).