Math

QuestionSimplify: 657\frac{6}{5-\sqrt{7}}. Choose the correct answer: a. 5+73\frac{5+\sqrt{7}}{3} b. 5+76\frac{5+\sqrt{7}}{6} c. 5+718\frac{5+\sqrt{7}}{18} d. 15+3715+3 \sqrt{7}.

Studdy Solution

STEP 1

Assumptions1. We are given the expression 657\frac{6}{5-\sqrt{7}} and we need to simplify it completely.

STEP 2

To simplify this expression, we need to rationalize the denominator. We do this by multiplying the numerator and the denominator by the conjugate of the denominator. The conjugate of a binomial expression aba - b is a+ba + b. So, the conjugate of 575 - \sqrt{7} is 5+75 + \sqrt{7}.
657×5+75+7\frac{6}{5-\sqrt{7}} \times \frac{5 + \sqrt{7}}{5 + \sqrt{7}}

STEP 3

Now, we multiply the numerator and the denominator separately.
6(5+7)(57)(5+7)\frac{6(5 + \sqrt{7})}{(5-\sqrt{7})(5 + \sqrt{7})}

STEP 4

We simplify the numerator and the denominator separately. In the denominator, we use the formula (ab)(a+b)=a2b2(a-b)(a+b) = a^2 - b^2.
30+672(7)2\frac{30 +6\sqrt{7}}{^2 - (\sqrt{7})^2}

STEP 5

implify the denominator.
30+7257\frac{30 +\sqrt{7}}{25 -7}

STEP 6

implify the denominator.
30+618\frac{30 +6\sqrt{}}{18}

STEP 7

We can simplify this further by dividing each term in the numerator by6.
5+73\frac{5 + \sqrt{7}}{3}So, the simplified form of the given expression is 5+73\frac{5 + \sqrt{7}}{3}, which corresponds to option (a).

Was this helpful?

Studdy solves anything!

banner

Start learning now

Download Studdy AI Tutor now. Learn with ease and get all help you need to be successful at school.

ParentsInfluencer programContactPolicyTerms
TwitterInstagramFacebookTikTokDiscord