Which equation is not an identity? (a.) tan(–t) = –tan t (b.) tan t(csc t + cot t) = sec t + 1 (c.) sin tcot t = cos t (d.) cos2t − sin2t = –1

  (D.)  cos²(t) − sin²(t) = –1

Step-by-step explanation:

The "Pythagorean identity" for sine and cosine is ...

  cos²(t) + sin²(t) = 1

Changing the sign makes it not be an identity.

A makes use of the fact that tangent is an odd function.

B makes use of cot=1/tan and tan=sec/csc.

C makes use of cot=cos/sin.

D has no relation to any definition or identity.

let's solve your equation step-by-step.

4x+2=2x+12

step 1: subtract 2x from both sides.

4x+2−2x=2x+12−2x

2x+2=12

step 2: subtract 2 from both sides.

2x+2−2=12−2

2x=10

step 3: divide both sides by 2.

2x

2

=

10

2

x=5

step-by-step explanation:

answer: 94

step-by-step explanation: 79+91+92+94+94 = 450 divided by 5 (since there are 5 number that are being added) = 90