more math level 2 question help please!

Archive SAT Subject Test Preparation
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^I knew that B, D, and E were entirely wrong-- but when I saw A and C, i got confused when trying to read the matrices! Could someone please explain the differences when interpreting matrices A and C?</p>

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^when I had my calculator in degree mode, and I did inverse sin and the value, i got a really strange number; but when I entered the values in RAD mode, I got E. How am I supposed to know that this question requires RAD mode? </p>

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<p>Q1: I isn’t true (there is a negative correlation). II is true (plug in F = 20), and III is true. D.</p>

<p>Q2: Matrix multiplication is not commutative. Keep that in mind…</p>

<p>Q3: It’s impossible to tell, other than “it’s implied.” Usually when the SAT uses pi as a trigonometric argument, it’s in radians. Also, radian measures do not use the degree symbol.</p>

<p>Q4: 2/5 = 48/L → L = 120. The length of the rope is sqrt(120^2 + 48^2) = 129.2439, D.</p>