Question

find the intercepts f(x)=x^2-6-x

Answer 1

x=-2,3, y=-6

Answer 2

can you explain how you got this

Answer 3

the x intercepts are when y = 0
so x^2-6-x = 0
which can be factored;
(x-3)(x+2) = 0
so the intercepts are at 3 and -2
the y intercept occurs when x = 0
so plugging x=0 in the expression:
y = 0 - 0 - 6 = -6

Answer 4

ok?

Answer 5

yes can you help me find the intercepts of f(x)=2x^2-3x+5

Answer 6

ok
first do you know how to factor f(x) ?

Answer 7

no

Answer 8

ok well this requires some practice but if you do that you'll get it
this type of expression is called a quadratic - there is 1 ^x , one term in x and one number
first the 2x^2 = 2x multiplied by x so we can write

(2x )(x )
now we want the other two numbers:

these two numbers are +1 and -5 because you want to get -3x in the middle and 2x1
and 1x -5 gives this so

we have (2x - 5)(x + 1) are our factors

this is hard to grasp at first for most people . you can find details on the wolframalpha website where it is explained very well

Answer 9

how about f(x)=3x^2+2x-5

Answer 10

so back to the problem
2x - 5)(x + 1) = 0
which gives 2x-5 = 0 and so x = 2.5
and x+1 = 0 so x = -1

in tercepts on x axis are -1,2-5

y intersept is when x = 0
this is y = 0 + 0 + 5
= 5

Answer 11

sorry -1, 2.5 and 5

Answer 12

ok thanks

Answer 13

can you answer my next question

Answer 14

ok

Answer 15

evaluate \[f(x)=\sin^2x+\cos^2x, x=9\pi/4\]

Answer 16

well sin^2x+cos^2x is always = 1 whatever value x is given so there is no need to evaluate it

Answer 17

that is a crafty question

Answer 18

why

Answer 19

well as i said that f(x) is always = 1, if this is written homework just plug in x=9pi/4 into the expression and write '= 1'.

Answer 20

and you'll get full credit for it

Answer 21

ok can you help me with \[(2/\cos \theta)+(4/1-\sin \theta)\]

Answer 22

what do u want to do with this - simplify it?

Answer 23

yes

Answer 24

do you have an answer for this

Answer 25

hmmm
(2/cosθ)+(4/1−sinθ)
= 2 - 2sinθ + 4cosθ / cosθ(1-sinθ)

thats what i've got so far but i 'm struggling a bit - hold on a bit

Answer 26

ok thank you for your help

Answer 27

thats ok - try posting that again - i might have missed the way to do this

Answer 28

\[(2/\cos \theta)+(4/1-\sin \theta)\]

Answer 29

is this good

Answer 30

can you plz help me no one else seems to know the answer to this question