SAT Math Hard Question!!!!

Test Preparation SAT Preparation
1

<p>Let the function f be defined by f(x)=2x+1. If 1/2f(sqrtT)=4, what is the value of T?</p>

<p>A. 3/sqrt2
B. 7/2
C. 9/2
D. 49/4
E. 81/4</p>

2

<p>the answer is 49/4</p>

<p>f(x)= 2x+1</p>

<p>so, f(s. T) = 2s.T+1
1/2 f(s. T) = s.T+.5</p>

<p>now, s.T+.5 = 4
, s.T = 3.5 or 7/2</p>

<pre><code>so, T = 49/4
</code></pre>

3

<p>it says the answer is E…</p>

4

<p>the answer is wrong.</p>

5

<p>This is from the Blue Book, page 970, but it’s transcribed wrong. It should be 2x – 1, not 2x + 1.</p>