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1-Visitor
May 4, 2015
Question

Mathcad 15 for Trigonometry - finding all values of angles

  • May 4, 2015
  • 3 replies
  • 2910 views

Hi - I'm wondering if someone could help me please on the following couple of questions regarding finding values of angles.

First one is 2sin^2(2x)+4sin(2x)=3.729, second one is cos(56-3x)=-0.783 (56 is in degrees)

For both of these find all the values for x between 0 and 360 (deg)

Thank you - I'm struggling with how far Mathcad can help me here in terms of re-arranging. It seems easy to type in the equations and click on x and then 'SOLVE' however I think I'm doing something wrong .....

Would appreciate any help

thank you

3 replies

19-Tanzanite
May 4, 2015

where _n is any integer number (including zero)

19-Tanzanite
May 4, 2015

Perhaps this will help:

trig.PNG

.

23-Emerald V
May 4, 2015

Ooh! Cat Skinning Time!

Let's generalize it a little ...

Stuart

The attached worksheet shows an 'assume real' symbolic solution further down the worksheet that avoids the need for the pickReal function, but does take up rather a lot of space (could always be hidden in a collapsed Area, though).

ccoldham1-VisitorAuthor
1-Visitor
May 4, 2015

Thank you Stuart - gosh I didn't realise it was so complicated !!!!

1-Visitor
May 4, 2015

Its easier than you think 😉

Gonio1.png

You may wish to sort the resulting vectors using the built-in command "sort".

ccoldham1-VisitorAuthor
1-Visitor
May 5, 2015

Wow - thank you so much Leopold