Cracking the SAT Subject Test in Math 2, 2nd Edition DEFINITIONS Here are some basic definitions that you will need to know for the SAT Subject Test in Math 2 Make sure you’re familiar with them If th[.]
DEFINITIONS Here are some basic definitions that you will need to know for the SAT Subject Test in Math Make sure you’re familiar with them If the meaning of any of these vocabulary words keeps slipping your mind, add that word to your flash cards Acute Angle An angle whose measure in degrees is between 0 and 90, exclusive Obtuse Angle An angle whose measure in degrees is between 90 and 180, exclusive Theta The symbol θ (pronounced thay-tuh) is a variable, just like x and y, used to represent the measure of an angle in trigonometry arc– Prefix added to trigonometric functions, meaning inverse THE BASIC FUNCTIONS The basis of trigonometry is the relationship between the parts of a right triangle When you know the measure of one of the acute angles in a right triangle, you know all the angles in that triangle For example, if you know that a right triangle contains a 20° angle, then you know all three angles—the right triangle must have a 90° angle, and because there are 180° in a triangle, the third angle must measure 70° You don’t know the lengths in the triangle, but you know its shape and its proportions A right triangle that contains a 20° angle can have only one shape, though it can be any size The same is true for a right triangle containing any other acute angle That’s the fundamental idea of trigonometry Once you know the measure of an acute angle in a right triangle, you know that triangle’s proportions