Question

am nevoie de ajuntor la exercitiul 1 si 3 atat urgent va rogggggvgggb​

Answer 1

Răspuns:

Explicație pas cu pas:

1.

sin^2 x + cos^2 x = 1

sin^2 x = 1 - cos^2 x = 1 - 4/9 = 9/9 - 4/9 = 5/9

cos x = √5/3

tg x = sin x / cos x = 2/3 : √5/3 = 2/3 * 3/√5 = 2/√5 = 2√5/5

ctg x = cos x / sin x = √5/3 : 2/3 = √5/3 * 3/2 = √5/2

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3.

f(x) = -2x + 1

f(-1) = 2 + 1 = 3

f(0) = 1

f(1) = -2 + 1 = -1

f(-1) + f(0) + f(1) = 3 + 1 - 1 = 3

f(x) = x

-2x + 1 = x

x + 2x = 1

3x = 1

x = 1/3