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Questions 1-5 please!
maths functions

Questions 1-5 please! maths functions-example-1
User Thomas Weber
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1 Answer

10 votes
10 votes

Answer:

1) x < -1

2) x ≥ -1

3) x ≤ -1

4) x < -1 and x > 0

5) -1 < x < 0

Step-by-step explanation:

(1) f(x) > 0


\sf \rightarrow \left((1)/(2)\right)^x-2 > \:0


\sf \rightarrow \left((1)/(2)\right)^x > \:2


\sf \rightarrow \left((1)/(2)\right)^x > \:2^(-1)


\sf \rightarrow x < -1

(2) f(x) ≤ 0


\sf \rightarrow \left((1)/(2)\right)^x-2 \leq \:0


\sf \rightarrow \left((1)/(2)\right)^x \leq \:2


\sf \rightarrow \left((1)/(2)\right)^x \leq \:2^(-1)


\sf \rightarrow x\geq -1

(3) g(x) ≥ 0


\sf \rightarrow -(2)/(x)-2 \:\geq \:0


\sf \rightarrow -(2)/(x) \:\geq \:2


\sf \rightarrow (1)/(x) \:\geq \:-1


\sf \rightarrow x \: \leq \:-1

(4) g(x) < 0


\sf \rightarrow -(2)/(x)-2 \: < \: 0


\sf \rightarrow x < -1 \ or \ x > 0

Observe the graphs a find solution for g(x) < 0

(5) f(x) < g(x)


\sf \rightarrow \left((1)/(2)\right)^x-2 < -(2)/(x)-2


\sf \rightarrow -1 < x < 0

User Akshaykarthik
by
2.8k points
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