okay so today is 1 of 2 spring break blog. the next one will be done before monday. today i am teaching you ch 8-4 which is relationships amoung trig functions. this is the section with all of the identities and stuff. so there are 3 identities:
1) sin^2 x + cos^2 x = 1
2) 1 + tan^2 x = sec^2x
3) 1 + cot^2 x = csc^2 x
there are also 4 steps which are to be followed loosely:
1) Algebrea
2) Use pythagorean identites and switch everything to sin and cos
3) Algebra
4) Repeat
EX:
simpilify sin^2 x + cos^2 x / cot x sin x
algebra cant be done
the numerator is an identity so it becomes 1/ cot x sin x
now you switch to sin and cos and it becomes 1 / (cos/sin)(sin)
your sines cancel and its 1 / cos = sec x
No comments:
Post a Comment