need help

[acoustic basin]

Need help with this

[split haven]

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[near roost]

find 1/a and rationalise it @acoustic basin

then square both a and 1/a and add them

[acoustic basin]

ok wait

Wait

Is 1/a=2√5/2?

@near roost

Is the answer 23/2

[near roost]

Nope

can you show your work?

[near roost]

shouldnt it be $\frac{3-\sqrt{5}}{2}$

[sleek yoke]

wolfqz

[near roost]

the 1/a rationalised form

[acoustic basin]

Lemme try again

@near roost I got it

[near roost]

yes

now do a^2 + 1/a^2

[acoustic basin]

Okay

Is the answer 9

[viral valve]

You could also say that a^2+1/a^2=(a+1/a)^2-2 no?

[acoustic basin]

U mean like this

?

[viral valve]

Not exactly

It’s((a+1/a)^2)-2

You subtract the last 2 from the whole thing

[acoustic basin]

Why Im not getting it

[near roost]

uh he means

[acoustic basin]

Is the answer 9

[near roost]

$\left(a+\frac{1}{a}\right)^2-2$

[near roost]

not exactly no

[sleek yoke]

wolfqz

[near roost]

this is the thing youre trying to get

[acoustic basin]

why -2

[near roost]

um see

$\left(a+\frac{1}{a}\right)^2 = a^2 + \frac{1}{a^2} + 2 \times a \times \frac{1}{a}$

[sleek yoke]

wolfqz

[acoustic basin]

we have to apply the formula

I see

(a+b)² = a² + 2ab + b²

?

[near roost]

ye

[acoustic basin]

Hey i gtg now I'll work on this latee

I have coaching class

+close