For a translation of English "Perspective". Google Translate says "Perspective" but my previous experience in French says that English words ending with "ive" end with "if" in French. I tried Google searching "Perspectif" and got some dictionary results, but they also mention "Perspective".
The rule is for French adjectives that end with -if at the masculine to end with -ive at the feminine, e.g..
actif / active
affirmatif / affirmative
aggressif / aggressive
décisif / décisive
On the other hand, nouns in -if/-ive, often substantivated adjectives, generally exists with a single gender and their ending match it, e.g.:
Some nouns (referring to persons) exist with both genders:
Un sportif/une sportive
Un fugitif/une fugitive
Un juif/une juive
There is also un esquif/une esquive where the nouns have an unrelated etymology and different meanings.
Finally, there are very few gender/ending mismatches:
Une manif1 (here just because it is a short form of une manifestation)
Détective is likely masculine simply because it was borrowed "as is" from English and there was only male detective at that time. Nowadays, it is definitely possible to say une détective when talking about a woman.
1Nouns not derived from an adjective.