For the function y=f(x)=(x^2-9)/(2x^2-5x-3) find f(sqrt2) with only one sqrt in your answer. 2. Find all x such that f(x)=-1 for same func.
Rewriting expressions with negative exponents?
- Posted:
- 3+ months ago by scfuller73
- Topics:
- mathematics
Details:
Answers (1)
A big part of math is pattern recognition. A lot of homework is just fighting with stuff so you will remember the pattern when you see it again. The most common pattern is (x + a) * (x + b) = x^2 + (a + b)x + ab and the special case (x + a) * (x - a) = x^2 - a^2. When you spot the pattern you can just write the answer from memory.
Now study this page until it seems obvious:
en.wikipedia.org/wiki/Polynomial_remainder_theorem
y=(x^2-9)/(2x^2-5x-3) Add spaces to improve readability.
y = (x^2 - 9)/(2x^2 - 5x - 3) Sub x = √2 and evaluate.
y = -7/(1 - 5√2) Multiply by (1 + 5√2)/(1 + 5√2)
y = (-7 - 35√2)/-49 Simplify.
y = (1 - 5√2)/7 <-- ANSWER