120 minutes
Step by step:
divide 20 by 2.5 to find how many minutes it takes to drive 1 mile, then multiply that by 15 miles
Answer:
Any value of x x makes the equation true. All real numbers Interval Notation: ( − ∞ , ∞ )
.
Option a:
is the equivalent expression.
Explanation:
The expression is
where 
Let us simplify the expression, to determine which expression is equivalent from the four options.
Multiplying the powers, we get,

Cancelling the like terms, we have,

This equation can also be written as,

Multiplying the terms in denominator, we have,

Thus, the expression which is equivalent to
is 
Hence, Option a is the correct answer.
<span><span>(<span>sinx</span>−<span>tanx</span>)</span><span>(<span>cosx</span>−<span>cotx</span>)</span></span>
<span>=<span>(<span>sinx</span>−<span><span>sinx</span><span>cosx</span></span>)</span><span>(<span>cosx</span>−<span><span>cosx</span><span>sinx</span></span>)</span></span>
<span>=<span>sinx</span><span>(1−<span>1<span>cosx</span></span>)</span><span>cosx</span><span>(1−<span>1<span>sinx</span></span>)</span></span>
<span>=<span>sinx</span><span>(<span><span>cosx</span><span>cosx</span></span>−<span>1<span>cosx</span></span>)</span><span>cosx</span><span>(<span><span>sinx</span><span>sinx</span></span>−<span>1<span>sinx</span></span>)</span></span>
<span>=<span><span>sinx</span><span>cosx</span></span><span>(<span>cosx</span>−1)</span><span><span>cosx</span><span>sinx</span></span><span>(<span>sinx</span>−1)</span></span>
<span>=<span>(<span>cosx</span>−1)</span><span>(<span>sinx</span>−1<span>)</span></span></span>