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If (log)3x=a and (log)7x=b , then which ...

If `(log)_3x=a` and `(log)_7x=b ,` then which of the following is equal to `(log)_(21)x ?` `a b` (b) `(a b)/(a^(-1)+b^(-1))` `1/(a+b)` (d) `1/(a^(-1)+b^(-1))`

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If (log)_3x=aa n d(log)_7x=b , then which of the following is equal to (log)_(21)x ? a. a b b. (a b)/(a^(-1)+b^(-1)) c. 1/(a+b) d. 1/(a^(-1)+b^(-1)

If (log)_4 5=aa n d(log)_5 6=b , then (log)_3 2 is equal to 1/(2a+1) (b) 1/(2b+1) (c) 2a b+1 (d) 1/(2a b-1)

If (log)_4 5=aa n d(log)_5 6=b , then (log)_3 2 is equal to 1/(2a+1) (b) 1/(2b+1) (c) 2a b+1 (d) 1/(2a b-1)

The domain of the following function is f(x)=(log)_2(-(log)_(1/2)(1+1/((x^(1/4)))-1) (0,1) (b) (0,1) (1,oo) (d) (1,oo)

If (log)_(10)2=a ,(log)_(10)3=bt h e n(log)_(0. 72)(9. 6) in terms of a and b is equal to (a) (2a+3b-1)/(5a+b-2) (b) (5a+b-1)/(3a+2b-2) (c) (3a+b-2)/(2a+3b-1) (d) (2a+5b-2)/(3a+b-1)

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