Given that 2 x = 9 and 2 7 y = 2 find the value of 3 x y .
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Great solution keep up the good work!
But here's a simpler method, instead of using logarithms, we can do this:
3 3 y 3 3 x y but 2 x ∴ 3 3 x y ⟹ 3 x y = 2 = 2 x = 9 = 9 = 3 2 = 2
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Good work !
good sravanth
Did the same way :D
I did it in the same way but I feel like the way you explained it is much better 😂😂😂
learn from sravanth teo
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I'm not criticizing his solution, I just pointed out a simpler method. Please don't take it otherwise ;)
taking logrithm on both sides for both eqns.. we get x= (2log3)/log2 and y=log2/(3log3) multiplying x and y we get x*y= 2/3 therefore 3xy= 3x2/3 = 2 answer...
2^x=9
2^x=3^2
2=3^(2/x)
27=2
3^3y=2
3^3y=3^(2/x)
3y=2/x
3yx=2
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Since we know 2 x = 9 , we can rewrite that as lo g 2 9 = x . Also, since 2 7 y = 2 we know 3 3 y = 2 which can be rewrite as lo g 3 2 = 3 y . Now, we see that we should convert the first equation to base three, which gives us lo g 3 2 lo g 3 9 By multiplying 3 y and x , we actually multiply lo g 3 2 and lo g 3 2 lo g 3 9 , leaving us with lo g 3 9 = 2