Wednesday, 5 June 2013

EXPONENTIAL EQUATIONS-1




If  32y-1 = 128y ; find y

Solution

32y-1 = 128y     Find prime factors of 32 and 128.

(25)y-1= (27)y   multiply the powers.



25y-5 = 27y   when bases are alike they cancel out.

25y-5 = 27y

5y – 5 = 7y       simple algebra

5y – 7y = 5

-2y = 5

  - 2y   =  5
  - 2        -2

y = 5/-2

Hence y =5/-2      


 

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