Question

please answer the question​

Answer 1

Answer:

The correct answer is-

1. a = 47/2
2. b = 21/2

Step-by-step explanation:

Refer the attached image.

Adiós! Hope this helps you.

Answer 2

Given:–

• 7+3√5 / 7-3√5 = a+b√5

To find:–

• We have to find values of a and b

Topic:–

• Rationalisation

Step by step explaination:–

First we have to multiply the given no. from each other. (i.e. rationalise)

➠ (7+3√5)(7+3√5) / (7-3√5)(7+3√5) = a+b√5

Now using the given identities to solve further:-

• (a+b)(a+b) = (a+b)²
• (a-b)(a+b) = a² - b²

Solving..

➠ (7+3√5)² / (7²-3√5)² = a+b√5

Opening brackets.

➠ 49 + 45+ 42√5 / 49-45 = a+b√5

Solving further.

➠ 94+42√5 / 4 = a+b√5

➠ 47 + 21√5 / 2 = a+b√5

At last separating them.

➠ 47/2 + 21√5/2 = a+b√5

Hence,

• a = 47/2
• b = 21/2
• b√5 = 21√5/2