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Help meeeeee plssss with steps​

Help meeeeee plssss with steps​-example-1
User Dharanbro
by
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1 Answer

7 votes

Answer:

p = 18, q = 0

Explanation:

The expression on the left side of the equation is

\large \text {$ (√(5)+\:2)/(√(5)-2)+(√(5)-\:2)/(√(5)+2) $}

Multiply the denominators to get a common denominator:


\text{$\left(√(5)-2\right)\left(√(5)+2\right)$}

=
\left(√(5)\right)^2-2^2 ∵ (a + b)(a - b) = a² - b²


=5-4\\\\= 1


\large \text {$ (√(5)+\:2)/(√(5)-2)+(√(5)-\:2)/(√(5)+2) $}\\\\


=(\left(√(5)+2\right)\left(√(5)+2\right))/(\left(√(5)-2\right)\left(√(5)+2\right)) + (\left(√(5) - 2\right)\left(√(5) - 2\right))/(\left(√(5)-2\right)\left(√(5)+2\right))

Since denominator

\text{$\left(√(5)-2\right)\left(√(5)+2\right)$} = 1,

the expression becomes


=\left(√(5)+2\right)^2 + \left(√(5)-2\right)^2\\\\= 5 + 4√(5) + 4 + 5 - 4√(5) + 4\\\\


= 10 + 8 = 18

Therefore

\large \text {$ (√(5)+\:2)/(√(5)-2)+(√(5)-\:2)/(√(5)+2) = p + q√(5)$}\\\\\\= > \large \text{$ 18 = p + q√(5)$}

Now
√(5) is an irrational number and p = rational so since there is no
√(5) term on the left side, q = 0 and p = 18

User Ryan Ferretti
by
4.3k points