X-intercept is -1 implies line passes through (-1,0).
So point slope form is
y - 0 = -2 (x -(-1) )
>> y = -2 (x +1) <----- FINAL ANSWER
Answer:
Students should be able to find the x-intercepts of a quadratic function using both factoring and completing the square. All that should be given to students is the standard form of a quadratic equation in the form y = ax^2 + bx + c.
Step-by-step explanation:
Answer:
sin²x = (1 - cos2x)/2 ⇒ proved down
Step-by-step explanation:
∵ sin²x = (sinx)(sinx) ⇒ add and subtract (cosx)(cosx)
(sinx)(sinx) + (cosx)(cosx) - (cosx)(cosx)
∵ (cosx)(cosx) - (sinx)(sinx) = cos(x + x) = cos2x
∴ - cos2x + cos²x = -cos2x + (1 - sin²x)
∴ 1 - cos2x - sin²x = (1 - cos2x)/2 ⇒ equality of the two sides
∴ (1 - cos2x) - 1/2(1 - cos2x) = sin²x
∴ 1/2(1 - cos2x) = sin²x
∴ sin²x = (1 - cos2x)/2