1 Verify the identity Simplify your answers completely 2Veri
1. Verify the identity. (Simplify your answers completely.)
2.Verify the identity.
tan(?) + cot(?) = sec(?) csc(?)
2a. Use a Reciprocal Identity to rewrite the expression in terms of sine and cosine as a single rational expression.
2b. Then, use a Pythagorean Identity to rewrite the expression in terms of a single function, and then simplify.
3. Verfiy the identity.
(sec(t)-cos(t))/sec(t) = sin^2(t)
3a. Use a Reciprocal Identity to rewrite the expression in terms of cosine only, and then simplify.
Solution
1. 5csc(-x)/sec(-x) = -5cot(x)
LHS : we know cscx = 1/sinx ; secx = 1/cosx
cos(-x) = cosx ; sin(-x) = sinx
Now 5csc(-x)/sec(-x) = 5
-5cosx/sinx = -5cotx
2) tan + cot = sec*csc
Use a Reciprocal Identity to rewrite the expression in terms of sine and cosine as a single rational expression.
tan + cot = sec*csc
sin/cos + cos/sin = 1(cos*sin)
LHS :sin/cos + cos/sin
= (sin^2+cos^2)/sincos
= 1/sincos
= RHS
Now using pythogorean identity: 1/sincos
Use : Sin^2x +cos^2x =1 ---> cosx = sqrt( 1- sin^2x)
1/sincos = 1/sin*( 1- sin^2)^1/2
= (sin)^-1(1-sin2)^-1/2
Expressing the single function
Hence proved
