Question 889319
Subtract 2/9t^8-1/6t^7
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Find a common denominator.
The product always works: 9t^8*6t^7 = 54t^15
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{{{2/9t^8 - 1/6t^7}}} = 6t^7/DEN - 9t^8/DEN
= (12t^7 - 9t^8)/54t^15
= 3t^7*(4 - 3t)/54t^15
= {{{(4 - 3t)/18t^8}}}