If a, b, c, d, and x are nonzero numbers, which of the following conditions must be true for (ax)^61(bx)^21(cx)^14(dx)^6>0? Choices.
A) x > 0 B) a × b > 0 C) c × d > 0 D) a × d > 0 E) a × b < 0
The question becomes a^(61) *b ^(21) *c^(14) *d^6*x^(102) &gt;0   c^14 , d^6 , x^102 are positive no matter what the sign of c ,d and x respectively   =&gt;a^61 *b ^21 must me positive   =&gt; a*b should be positive   Ans a × b &gt; 0
<result>B</result>
If a, b, c, d, and x are nonzero numbers, which of the following conditions must be true for (ax)^61(bx)^21(cx)^14(dx)^6>0?