SOLUTION: The equation cos(x) = 0.3x has three solutions. Find their values correct to two decimal places

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Question 255215: The equation cos(x) = 0.3x has three solutions. Find their values correct to two decimal places
Answer by Edwin McCravy(20055) About Me  (Show Source):
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The equation cos(x) = 0.3x has three solutions.
Find their values correct to two decimal places

Make sure your TI-83 or 84 is in RADIAN mode:


Press CLEAR
Press MODE
Scroll down to RADIAN
Press ENTER
Press 2nd
Press MODE (QUIT)

Press Y=
beside \Y1=  type cos(X)
beside \Y2=  type .3X

Press ZOOM
Press 7
Press 2nd
Press TRACE (CALC)
Press 5
Press ENTER
Press ENTER
Press ENTER

Read the X-value:

X = 1.2019132  

That's one solution

Press TRACE (CALC)
Press 5

Press ENTER
Press ENTER

Press the left arrow key 20 times

Press ENTER

Read the X-value:

X = -2.355585 

That's the second solution.

Press TRACE (CALC)
Press 5

Press ENTER
Press ENTER

Press the left arrow key 10 times

Press ENTER

Read the X-value:

X = -3.294461

That's the third solution

Edwin