SOLUTION: Could someone please explain how to do this problem? Evaluate 3cos(cos70degrees + cos20degrees)squared - 3cos50degrees without using a calculator. All work must be done by hand

Question 283851: Could someone please explain how to do this problem?
Evaluate 3cos(cos70degrees + cos20degrees)squared - 3cos50degrees without using a calculator. All work must be done by hand on your answer sheet.
My trig is rusty and I am having some difficulties.
Thanks!
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
Evaluate 3cos(cos70degrees + cos20degrees)squared - 3cos50degrees without using a calculator.
------------------
3cos(cos70degrees + cos20degrees)
(cos70degrees + cos20degrees) is > 1. The cosine can't exceed 1 for real numbers.

RELATED QUESTIONS
factor completely Show your work 25y^4-36 I do not know how to do this problem... (answered by solver91311)

find the associated half life or doubling time. Q=1800e^-0.025t could someone please... (answered by Fombitz)

Could someone please explain how to do this problem and solve please? (2x to the 4th... (answered by arunpaul)

Could someone please help me with this problem? I need to Evaluate: (�3)(�6) + (4)(�2) (answered by mananth)

I do not understand how to solve systems of linear equations in three variables.... (answered by Fombitz,ktsau)

Please help! Evaluate the expression 12! using a calculator.... (answered by swincher4391,solver91311)

could you please help me solve this problem and also, explain in detail in the math... (answered by Theo)

I was wondering if someone could please explain to me how to do this. s=a/1-r solve... (answered by Fombitz)

Solve for x on the interval [0,2pi]. cos^2(x)+3cos(x)+2=0 Someone please help, (answered by ikleyn)