i am getting a)
The sum of roots of the equation
x + 1 - 2 log2 (2x + 3) + 2 log4 (10 - 2-x) = 0 is
a) log211
b) log212
c) log213
d) log214
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5 Answers
mohit_ sharma
·2012-03-28 05:30:37
x+1 - 4log4(2x+3)+2log4(10-2-x)=0
this gives
2-(x+1) = (10-2-x)/(2x+3)2
→ 22x -14.2x + 11=0
put 2x =t
this gives 2x =7± √38
x= log2(7±√38)
thus x1 + x2 =log211