If log 135 7=a and log 7 5=b, then log 35 105 is equal to

Question

If log 135 7=a and log 7 5=b, then log 35 105 is equal to (A) (a b+3 a+1/3 a(b+1)) (B) (a b+a+1/3 a(b+1)) (C) (2 a b+3 a+1/a(b+1)) (D) (2 a b+3 a+1/3 a(b+1))

Tardigrade Admin · Accepted Answer

Correct answer is (d) (2 a b+3 a+1/3 a(b+1))

Q. If $lo g_{135} 7 = a$ and $lo g_{7} 5 = b$ , then $lo g_{35} 105$ is equal to

$\frac{ab + 3 a + 1}{3 a ( b + 1 )}$

$\frac{ab + a + 1}{3 a ( b + 1 )}$

$\frac{2 ab + 3 a + 1}{a ( b + 1 )}$

$\frac{2 ab + 3 a + 1}{3 a ( b + 1 )}$

Correct answer is (d) $\frac{2 ab + 3 a + 1}{3 a ( b + 1 )}$

Q. If log135​7=a and log7​5=b, then log35​105 is equal to

3a(b+1)ab+3a+1​

3a(b+1)ab+a+1​

a(b+1)2ab+3a+1​

3a(b+1)2ab+3a+1​