Question

Let -pi/4 < x < pi/4 , f(x)=tan(2x). A tangent to the graph of y=f(x) where x= a makes an angle of 70 degrees with the positive direction of the x-axis. Find the possible values of a

Answer 1

x=a=70 degrees = 7pi/18

Answer 2

HINT :

slope = f'(a) = tan(70)

Answer 3

could you please explain it more i know that the gradient is equal to f'(a) but what i couldnt understand was tan(70)

Answer 4

whats the definition of "tan" ? remember SOH-CAH-TOA ?

Answer 5

opposite/adjacent

Answer 6

and whats the definition of slope ?

Answer 7

how do u get slope of a line ?

Answer 8

derivative

Answer 9

suppose you don't know calculus,
what would u do to get the slope of a line ?

Answer 10

slope = (y2-y1) / (x2 - x1)
right ?

Answer 11

y=mx+b

Answer 12

right