Question

pls help me by solving this ​

Answer 1

Answer:

ok wait a minute .... please

Answer 2

Answer:

Q9: a+1/a=18

a-1/a=8√5

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Q10: x+1/x=6

x²+1/x²=38

Step-by-step explanation:

Q9 a=9+4√5

(i) a +1/a

1/a=1/(9+4√5)

Multiplying the numerator and denominator by 9-4√5

=(9-4√5)/(9-4√5)(9+4√5)

1/a=(9-4√5) /(81-80)=9-4√5.............(1)

So a+1/a

=9+4√5+9-4√5=18

So a+1/a=18

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a-1/a=9+4√5-(9-4√5)=8√5

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Q10 x=3+2√2

1/x=1/3+2√2

=(3-2√2) / (3+2√2)(3-2√2)

1/x=(3-2√2) / (9-8)=(3-2√2)

Thus x+1/x=3+2√2+3-2√2=6

x+1/x=6

squaring both sides

x²+1/x²+2*1*1/x=6²

x²+1/x²=36-2=34