Math, asked by sreeja6335, 7 months ago

Find the value of a and b if

5-root3 upon root 5 + root 3 = (1/2) a + 3b root 15 ?

guys its urgent plz dont post any irrelevant answers I would really appreciate those who give the correct answer and mark as branliest​

Answers

Answered by Anonymous
13

Answer:

do let me know if its incorrect

Attachments:
Answered by smithasijotsl
1

Answer:

The value of a = 8 and the value of b =   \frac{-1}{3}

Step-by-step explanation:

Given,

\frac{\sqrt{5} - \sqrt{3} }{\sqrt{5} + \sqrt{3} }  = \frac{1}{2}a  + 3b\sqrt{15}

To find,

The value of 'a' and 'b'

Solution,

L H S = \frac{\sqrt{5} - \sqrt{3} }{\sqrt{5} + \sqrt{3} }

The rationalizing factor = \sqrt{5} - \sqrt{3}

Multiply the numerator and denominator with the rationalizing factor, we get

\frac{\sqrt{5} - \sqrt{3} }{\sqrt{5} + \sqrt{3} } ×\frac{\sqrt{5} - \sqrt{3} }{\sqrt{5} - \sqrt{3} } = \frac{(\sqrt{5} - \sqrt{3} )^2}{(\sqrt{5})^2 - (\sqrt{3})^2 }

=  \frac{((\sqrt{5})^2 + (\sqrt{3} )^2 - 2\sqrt{3}\sqrt{5}  }{5 - 3}

= \frac{5 + 3 - 2\sqrt{15} }{2}

= \frac{8 - 2\sqrt{15} }{2}

= 4 - \sqrt{15}

Since  \frac{\sqrt{5} - \sqrt{3} }{\sqrt{5} + \sqrt{3} }  = \frac{1}{2}a  + 3b\sqrt{15}, we have

4 - \sqrt{15} = \frac{1}{2}a  + 3b\sqrt{15}

Comparing the rational and irrationals on both sides we get,

4 = \frac{1}{2}a

a = 8

3b\sqrt{15} = -\sqrt{15}

3b = -1

b = \frac{-1}{3}

The value of a = 8 and the value of b =  \frac{-1}{3}

#SPJ2

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