30:60:90
3:6:9
1:2:3
I can’t make sense of given answers
Answer:
f(x) = sec x. tan x
⇔ f(x) = 1/cosx . cosx/sinx
⇔ f(x) = sin x
+) when f(x) is increasing => sin x increases
=> x will increase
+) f(x) is decreasing => x will decrease
+) f(x) is concave up => x ∈ (-pi/2; 0)
+) f(x) concave down => x ∈ (0; pi/2)
Step-by-step explanation:
Answer:
The answer is 
Step-by-step explanation:
to solve this inequality:

Put "-7" on both sides

divide by 5 on both sides
your answer should be 2.