The discussion revolves around expressing the value of cosine(0.9812) in two different ways using radians, with a focus on calculator-based methods.
Some participants have provided insights into the periodic nature of the cosine function and its even property, suggesting that there are indeed multiple angles that yield the same cosine value. However, there is no explicit consensus on how to express these angles in two distinct ways.
There appears to be some confusion regarding the original question, with participants questioning whether the inquiry pertains to cos(0.9812) or cos-1(0.9812). The discussion also highlights the constraints of calculator-based solutions.
thearn said:Homework Statement
how would you write cosine(.9812) in two ways expressed with radians
(calculator based)
Homework Equations
cos-1(x)
The Attempt at a Solution
i just plugged cos-1(.9812) and got .1942 radians. If this is one of the answers how do i find the other.
Do you mean cos-1(.9812)? That's what your work below suggests.thearn said:Homework Statement
how would you write cosine(.9812) in two ways expressed with radians
(calculator based)
cos(.1942 radians) [itex]\approx[/itex] .9812, but there are many angles whose cosine is also .9812. The cosine function is periodic, with period 2π, so adding 2π or integer multiples of 2π gives you an angle with the same cosine value. The cosine function is also and even function, which means that cos(-x) = cos(x), for any real x.thearn said:Homework Equations
cos-1(x)
The Attempt at a Solution
i just plugged cos-1(.9812) and got .1942 radians. If this is one of the answers how do i find the other.