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Fredrick Jerde

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โˆ™ 2021-03-01 17:57:15
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A polynomial of degree zero is a constant term

The grouping method of factoring can still be used when only some of the terms share a common factor A True B False

The sum or difference of p and q is the of the x-term in the trinomial

A number a power of a variable or a product of the two is a monomial while a polynomial is the of monomials

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โˆ™ 2010-05-05 21:24:54

When proving an identity, you may manipulate only one side of the equation throughout. You may not use normal algebraic techniques to manipulte both sides. Let's begin with the identity you wish to prove. cos2x - sin2x ?=? 2cos2x - 1 We know that sin2x + cos2x = 1 (Pythagorean Identity). Therefore, sin2x = 1 - cos2x. Substituting for sin2x, we may write cos2x - (1 - cos2x) ?=? 2cos2x - 1 cos2x - 1 + cos2x ?=? 2cos2x - 12cos2x -1 = 2cos2x - 1 The identity is proved. (Note that once the identity is proved, you may remove the question marks from around the equal sign.)

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Q: Can you prove that cossquaredx - sinsquaredx equals 2cossquaredx -1?
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