2. prove that the vectors are orthogonal unit vectors for any value of 0 u = (coso,-sino), v = (sino, cos)

Because u·v=0 they are orthogonal

Step-by-step explanation:

Let's find the solution by using the dot product, taking into account that two vectors are orthogonal if its dot product is equal to 0, so:

u=(cos(o),-sin(o))

v=(sin(o),cos(o))

Let's find the dot product:

u·v=(cos(o),-sin(o))*(sin(o),cos(o))

u·v=cos(o)*sin(o)+(-sin(o)*cos(o))

u·v=cos(o)*sin(o)-sin(o)*cos(o)

u·v=0

In conclusion, for any value of o, u·v=0. So u and v are orthogonal.

answer: 75°

step-by-step explanation:

∠esk is the supplement of ∠edk, so is 100°. ∠esd = 1/2·arc ed, so is 25°.

since ∠esk = ∠esd + ∠dsk

you have 100° = 25° + ∠dsk . .

fill in known values 75° = ∠dsk . . . . .

subtract 25°

step-by-step explanation:

you are playing an adventure game on your computer. you come across a troll who won't let you pass and there is no other way to get to the other side of the river except over the bridge he is guarding.

the troll is a nerd. he takes great delight in watching people struggle with his problems. very few get them. he only gives you one chance and then he changes the puzzle. you have to solve this one.

before you are four blocks. they are numbered 11,6, -7,21.

he tells that the answer he wants is minus and between -1 and - 2. you can use +, -, ×, ÷   ( and ) as many times as you like or no times at all. you don't like the way he's looking at you, but you need to cross the bridge. what do you do?